Руководство на дэу нубира скачать

Войдите или зарегистрируйтесь, чтобы писать комментарии, задавать вопросы и участвовать в обсуждении.

• Contents

• Table of Contents

• Bookmarks

Summary of Contents for Daewoo Nubira

SECTION : 0B

GENERAL INFORMATION

TABLE OF CONTENTSSPECIFICATIONS 0B–1. . . . . . . . . . . . . . . . . . . . . . . . . .

TECHNICAL DATA 0B–1. . . . . . . . . . . . . . . . . . . . . . . .

VEHICLE DIMENSIONS AND WEIGHTS 0B–5. . . . .

STANDARD BOLT SPECIFICATIONS 0B–7. . . . . . . .

MAINTENANCE AND REPAIR 0B–8. . . . . . . . . . . . . . .

MAINTENANCE AND LUBRICATION 0B–8. . . . . . . . . .

NORMAL VEHICLE USE 0B–8. . . . . . . . . . . . . . . . . . .

EXPLANATION OF SCHEDULED MAINTENANCESERVICES 0B–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SCHEDULED MAINTENANCE CHARTS 0B–10. . . .

OWNER INSPECTIONS AND SERVICES 0B–12. . . . .

WHILE OPERATING THE VEHICLE 0B–12. . . . . . . .

AT EACH FUEL FILL 0B–12. . . . . . . . . . . . . . . . . . . . . .

AT LEAST MONTHLY 0B–12. . . . . . . . . . . . . . . . . . . . .

AT LEAST TWICE A YEAR 0B–12. . . . . . . . . . . . . . . .

EACH TIME THE OIL IS CHANGED 0B–13. . . . . . . .

AT LEAST ANNUALLY 0B–13. . . . . . . . . . . . . . . . . . . .

RECOMMENDED FLUIDS AND LUBRICANTS 0B–15

GENERAL DESCRIPTION AND SYSTEMOPERATION 0B–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

GENERAL REPAIR INSTRUCTIONS 0B–16. . . . . . .

GENERAL DESCRIPTION 0B–17. . . . . . . . . . . . . . . . . .

ON BOARD REFUELING VAPOR RECOVERYSYSTEM 0B–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

VEHICLE IDENTIFICATION 0B–20. . . . . . . . . . . . . . .

VEHICLE LIFTING PROCEDURES 0B–24. . . . . . . . .

SPECIFICATIONS

TECHNICAL DATA

Performance – Manual Transaxle

Application 2.0L DOHC

Maximum Speed 195 km/h (122 mph)

Gradeability 0.446 (tan Ø)

Minimum Turning Radius 5.3 m (17 ft)

Performance – Automatic Transaxle

Application 2.0L DOHC

Maximum Speed 190 km/h (119mph)

Gradeability 0.668 (tan Ø)

Minimum Turning Radius 5.3 m (17 ft)

0B – 2IGENERAL INFORMATION

DAEWOO V–121 BL4

Engine

Application 2.0L DOHC

Engine Type Dual Overhead Cam L–4

Bore 86 mm (3.4 in.)

Stroke 86 mm (3.4 in.)

Total Displacement 1 998 cm3 (121.9 in3)

Compression Ratio 9.5µ0.2:1

Maximum Power 96 kW (128.7 bhp)(at 5,400 rpm)

Maximum Torque 184 Nm (135.7 lb–ft)(at 4,400 rpm)

Ignition System

Application 2.0L DOHC

Ignition Type Direct Ignition System

Ignition Timing 8³ BTDC

Ignition Sequence 1–3–4–2

Spark Plug Gap 0.8 mm (0.031 in)

Spark Plug Maker Bosch

Spark Plug Type FR8LDC4

Clutch – Manual Transaxle

Application 2.0L DOHC

Type Single Dry Plate

Outside Diameter 225 mm (9.0 in.)

Inside Diameter 150 mm (5.9 in.)

Thickness 3.4 mm (0.13 in.)

Fluid Capacity Common Use; Brake Fluid

Manual Transaxle

Application 2.2L DOHC

Maker DWMC

Type or Model D–20

Gear Ratio: –

1st 3.545:1

2nd 2.158:1

3rd 1.478:1

4th 1.129:1

5th 0.886:1

Reverse 3.333:1

Final Drive Ratio 3.550:1

Oil Capacity 1.8L (2 qt)

* Puerto Rico only.

GENERAL INFORMATION 0B – 3

DAEWOO V–121 BL4

Automatic Transaxle

Application 2.0L DOHC

Maker GM

Type or Model 4T40E

Gear Ratio: –

1st 2.957:1

2nd 1.623:1

3rd 1.000:1

4th 0.682:1

Reverse 2.143:1

Final Drive Ratio 3.910:1

Oil Capacity 11.5L (12 qt)

Brake

Application 2.0L DOHC

Booster Size: –

Single 228.6 mm (9 in.)

Master Cylinder Diameter 22.2 mm (0.87 in.)

Booster Ratio 5.0:1

Front Brake: –

Disc Type Ventilated

Disc Size 356 mm (14.0 in.)

Rear Brake: –

Disc: –

Disc Type Solid

Disc Size 32 mm (1.3 in.)

Fluid Capacity 0.5L (0.53 qt)

Tire and Wheel

Application 2.0L DOHC

Standard Tire Size 185/65R14

Temporary Tire Size T125/70D15

Standard Wheel Size 5.5JX14

Inflation Pressure at Full Load: –

185/65R14: ––

Front 30 psi

Rear 28 psi

T127/70D15 60 psi

0B – 4IGENERAL INFORMATION

DAEWOO V–121 BL4

Steering System

Application 2.0L DOHC

Gear Type Power Rack and Pinion

Overall Gear Ratio: –

Manual Steering –

Power Steering 16:1

Wheel Alignment: –

Front: –

Total Toe–In (2 Occupants) –10′ to +10′

Caster: –

Power Steering 2³30′ to 3³30′

Camber –54′ to 6′

Rear: –

Total Toe–In (2 Occupants) –3′ to +17′

Camber –1³35′ to –5′

Oil Capacity 1.0L (1.1 qt)

Suspension

Application 2.0L DOHC

Front Type MacPherson Strut

Rear Type Compound Link

Fuel System

Application 2.0L DOHC

Fuel Delivery MPI

Fuel Pump Type Electric Motor Pump

Fuel Filter Type Cartridge

Fuel Capacity 52L (13.7 gal)

Lubricating System

Application 2.0L DOHC

Lubricating Type Forced Feed

Oil Pump Type Duocentric Rotor

Oil Filter Type Cartridge (Full Flow)

Oil Pan Capacity Including Oil Filter 3.8L (4.1 qt)

GENERAL INFORMATION 0B – 5

DAEWOO V–121 BL4

Cooling System

Application 2.0L DOHC

Cooling Type Forced Water Circulation

Radiator Type Cross–flow

Water Pump Type Centrifugal

Thermostat Type Pellet Type

Coolant Capacity: –

Manual: 7.0L (7.4 qt)

Automatic: 7.0L (7.4 qt)

Electric System

Application 2.0L DOHC

Battery (55 AH, M/F) 630 Cold Cranking Amps

Alternator: 85 Amps

Starter (1.4 kW) No Load Test Minimum 40 AmpsMaximum 90 Amps

(at 12.2 volts)

VEHICLE DIMENSIONS AND WEIGHTS

Vehicle Dimensions – Manual and Automatic

Application 2.0L DOHC

Overall Length: –

4–Door Notchback 4 470 mm (176.0 in.)

4–Door Wagon 4 514 mm (177.7 in.)

5–Door 4 248 mm (167.2 in.)

Overall Width 1 700 mm (66.9 in.)

Overall Height: –

4–Door Notchback 1 425 mm (56.1 in.)

4–Door Wagon 1 432 mm (56.4 in.)

5–Door 1 425 mm (56.1 in.)

Overall Height: Overall Height:

4–Door Notchback 1 430 mm (56.2 in.)

4–Door Wagon 1 470 mm (58.0 in.)

5–Door 1 430 mm (56.2 in.)

Minimum Ground Clearance 151 mm (5.9 in.)

Wheel Base 2 570 mm (101.2 in.)

Tread: –

Front 1 464 mm (57.6 in.)

Rear 1 454 mm (57.2 in.)

0B – 6IGENERAL INFORMATION

DAEWOO V–121 BL4

Vehicle Weights – 4 Door Notchback

Application 2.0L DOHC

Manual: –

Curb Weight: –

Standard 1 164 kg (2,566 lb)

Optional 1 233 kg (2,718 lb)

Gross Vehicle Weight 1 720 kg (3,792 lb)

Automatic: –

Curb Weight –

Standard 1 200 kg (2,645 lb)

Optional 1 269 kg (2,797 lb)

Gross Vehicle Weight 1 720 kg (3,792 lb)

Passenger Capacity 5

Vehicle Weights – 4 Door Wagon

Application 2.0L DOHC

Manual: –

Curb Weight: –

Standard 1 222 kg (2,694 lb)

Optional 1 291 kg (2,846 lb)

Gross Vehicle Weight 1 860 kg (4,101 lb)

Automatic: –

Curb Weight –

Standard 1 258 kg (2,773 lb)

Optional 1 327 kg (2,925 lb)

Gross Vehicle Weight 1 860 kg (4,101 lb)

Passenger Capacity 5

Vehicle Weights – 5 Door

Application 2.0L DOHC

Manual: –

Curb Weight: –

Standard 1 155 kg (2,546 lb)

Optional 1 224 kg (2,698 lb)

Gross Vehicle Weight 1 720 kg (3,792 lb)

Automatic: –

Curb Weight: –

Standard 1 191 kg (2,625 lb)

Optional 1 260 kg (2,778 lb)

Gross Vehicle Weight 1 720 kg (3,792 lb)

Passenger Capacity 5

Optional Weight: Air Conditioning, Power Steering, ABS, Sunroof, Airbag.

GENERAL INFORMATION 0B – 7

DAEWOO V–121 BL4

STANDARD BOLT SPECIFICATIONS

Bolt* 4T – Low Carbon Steel 7T – High Carbon Steel 7T – Alloy Steel

M6 X 1.0 4.1–8.1 Nm (36–72 lb–in) 5.4–9.5 Nm (48–84 lb–in) –

M8 X 1.25 8.1–17.6 Nm (72–156 lb–in) 12.2–23.0 Nm (108–204 lb–in)

16–30 Nm (12–22 lb–ft)

M10 X 1.25 20–34 Nm (15–25 lb–ft) 27–46 Nm (20–34 lb–ft) 37–62 Nm (27–46 lb–ft)

M10 X 1.5 19–34 Nm (14–25 lb–ft) 27–45 Nm (20–33 lb–ft) 37–60 Nm (27–44 lb–ft)

M12 X 1.25 49–73 Nm (36–54 lb–ft) 61–91 Nm (45–67 lb–ft) 76–114 Nm (56–84 lb–ft)

M12 X 1.75 45–69 Nm (33–51 lb–ft) 57–84 Nm (42–62 lb–ft) 72–107 Nm (53–79 lb–ft)

M14 X 1.5 76–115 Nm (56–85 lb–ft) 94–140 Nm (69–103 lb–ft) 114–171 Nm (84–126 lb–ft)

M14 X 2.0 72–107 Nm (53–79 lb–ft) 88–132 Nm (65–97 lb–ft) 107–160 Nm (79–118 lb–ft)

M16 X 1.5 104–157 Nm (77–116 lb–ft) 136–203 Nm (100–150 lb–ft) 160–240 Nm (118–177 lb–ft)

M16 X 2.0 100–149 Nm (74–110 lb–ft) 129–194 Nm (95–143 lb–ft) 153–229 Nm (113–169 lb–ft)

M18 X 1.5 151–225 Nm (111–166 lb–ft) 195–293 Nm (144–216 lb–ft) 229–346 Nm (169–255 lb–ft)

M20 X 1.5 206–311 Nm (152–229 lb–ft) 270–405 Nm (199–299 lb–ft) 317–476 Nm (234–351 lb–ft)

M22 X 1.5 251–414 Nm (185–305 lb–ft) 363–544 Nm (268–401 lb–ft) 424–636 Nm (313–469 lb–ft)

M24 X 2.0 359–540 Nm (265–398 lb–ft) 431–710 Nm (318–524 lb–ft) 555–831 Nm (409–613 lb–ft)

* Diameter X pitch in millimeters

0B – 8IGENERAL INFORMATION

DAEWOO V–121 BL4

MAINTENANCE AND REPAIRMAINTENANCE AND LUBRICATION

NORMAL VEHICLE USEThe maintenance instructions contained in the mainte-nance schedule are based on the assumption that the ve-hicle will be used for the following reasons: To carry passengers and cargo within the limitation

indicated on the Tire Placard located on the edge ofthe driver’s side door.

To be driven on reasonable road surfaces and with-in legal operating limits.

EXPLANATION OF SCHEDULEDMAINTENANCE SERVICESThe services listed in the maintenance schedule are fur-ther explained below. When the following maintenanceservices are performed, make sure all the parts are re-placed and all the necessary repairs are done before driv-ing the vehicle. Always use the proper fluid and lubricants.

Drive Belt InspectionWhen a separate belt drives the power steering pump, theair conditioning compressor, and the generator, inspect itfor cracks, fraying, wear, and proper tension. Adjust or re-place the belt, as needed.

Engine Oil and Oil Filter ChangeAPI Classifications of Engine OilThe International Lubricant Standardization and ApprovalCommittee (ILSAC) and American Petroleum Instituteclassifies engine oils according to their performance quali-ty. Always use oil rated API–SJ (ILSAC GF–II) or better.

Engine Oil ViscosityEngine oil viscosity (thickness) has an effect on fuel econ-omy and cold weather operation. Lower viscosity engineoils can provide better fuel economy and cold weather per-formance; however, higher temperature weather condi-tions require higher viscosity engine oils for satisfactory lu-brication. Using oils of any viscosity other than thoseviscosities recommended could result in engine damage.

Cooling System ServiceDrain, flush and refill the system with new coolant. Referto ”Recommended Fluids and Lubricants”in this section.

GENERAL INFORMATION 0B – 9

DAEWOO V–121 BL4

Fuel Micro–Filter ReplacementReplace the engine fuel filter every 48,000 km (30,000miles).The engine fuel filter is located on the center dash panelnear the brake booster.

Air Cleaner Element ReplacementReplace the air cleaner element every 48 000 km (30,000miles).Replace the air cleaner more often under dusty conditions.

Throttle Body Mounting Bolt TorqueCheck the torque of the throttle body mounting bolts.Tighten the throttle body mounting bolts to 17 Nm (13 lb–ft) if necessary.

Spark Plug ReplacementReplace spark plugs with the same type.

– Type: AC Type FR8LDC4 (2.0L DOHC)– Gap: 0.8 mm (0.031 in.) (2.0L DOHC)

Spark Plug Wire ReplacementClean the wires and inspect them for burns, cracks, or oth-er damage. Check the wire boot fit at the direct ignitionsystem (DIS) module and at the spark plugs. Replace thewires, as needed.

Brake System ServiceCheck the disc brake pads or the drum brake linings every9,600 km (6,000 mi) or 6 months. Check the pad and thelining thickness carefully. If the pads or the linings are notexpected to last another 9,600 km (6,000 mi), replace thepads or the linings. Check the breather hole in the brakefluid reservoir cap to be sure it is free from dirt and the pas-sage is open.

Transaxle ServiceThe manual transaxle fluid does not require changing. Forautomatic transaxles, refer to ”Scheduled MaintenanceCharts”in this section.

Tire and Wheel Inspection and RotationCheck the tires for abnormal wear or damage. To equalizewear and obtain maximum tire life, rotate the tires. If irreg-ular or premature wear exists, check the wheel alignmentand check for damaged wheels. While the tires andwheels are removed, inspect the brakes. Refer to ”EachTime The Oil Is Changed”in this section.

0B – 10IGENERAL INFORMATION

DAEWOO V–121 BL4

SCHEDULED MAINTENANCE CHARTS

Engine

Maintenance Item Maintenance Interval

Miles (Kilometers) or time inmonths, whichever comes first

x 1,000 miles 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102

x 1,000 km 9.6 19.2 28.8 38.4 48 57.6 67.2 76.8 86.46 96 105.6 115.2 124.8 134.4 144 153.6 163.2

# Months 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102

Drive belt (Generator and powerSteering)

I I I I I

Engine oil & engine oil filter (1)(3) R R R R R R R R R R R R R R R R R

Cooling system hose & connec-tions

I I I I I I I I

Engine coolant (3) I I I I R I I I I R I I I I R I I

Fuel filter R* R* R*

Fuel line and connections I* I* I* I* I* I* I* I*

Air cleaner element (2) I* I* I* I* R I* I* I* I* R I* I* I* I* R I* I*

Ignition timing I* I* I* I* I* I* I* I*

Spark plugs I* R I* R I* R

Evaporative emission canister &vapor lines

I* I* I*

PCV system I* I* I* I* I*

Camshaftbelt(Timimgbelt)

Out of Cali-fornia

Replace every 72,000 miles (115,200 km)

belt)

California Inspect every 60,000 miles (96,000 km) and 90,000 miles (144,000 km)Replace every 102,000 miles (163,200 km)

Chart Symbols:I – Inspect these items and their related parts. If necessary, correct, clean, replenish, adjust or replace.R – Replace or change.(1) Change the engine oil every 3,000 miles (4,800 kilometers) or 3 months, whichever comes first, if the vehicle is operatedunder any of the following conditions :

– Short–distance driving.– Extensive idling.– Driving on dusty roads.

(2) More frequent maintenance is required if driving under dusty conditions.(3) Refer to ”Recommended Fluids And Lubricants”Note : Check the engine oil and radiator coolant levels ev-ery week.* : Replacement or inspection of these emissions components is recommended to be performed at the indicated intervalshowever, the California Air Resources Board has determined that performing thesemaintenance items are not requiredto maintained your vehicle emission warranty.

GENERAL INFORMATION 0B – 11

DAEWOO V–121 BL4

Chassis and Body

Maintenance Item Maintenance Interval

Miles (Kilometers) or time inmonths, whichever comes first

x 1,000 miles 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102

x 1,000 km 9.6 19.2 28.8 38.4 48 57.6 67.2 76.8 86.46 96 105.6 115.2 124.8 134.4 144 153.6 163.2

# Months 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102

Air Filter (A/C) (2) R R R R R R R R R R R R R R R R R

Exhaust pipes & mountings I* I* I* I* I* I* I* I*

Brake/Clutch fluid (3)(5) I I R I I R I I R I I R I I R I

Brake pads & discs(6) I I I I I I I I I I I I I I I I

Parking brake I I I I I I I

Brake line & connections (In-cluding booster)

I I I I I I I I I I I I I I I I

Rear hub bearing & clearance I I I I I I I I

Manual Transaxle Oil (3) I I I I I I I I

Clutch & brake pedal free play I I I I I I I I I I I I I I I I I

Automatic transaxle fluid* (3) (7) I I I I R I I I

Chassis & underbody bolts &nuts, tighten/secure

I I I I I I I I I I I I I I I I I

Tire condition & inflation pres-sure

I I I I I I I I I I I I I I I I I

Wheel alignment (8) Inspect when abnormal condition is noted.

Tire rotation Rotate tires every 6,000 miles

Steering wheel & linkage I I I I I I I I I I I I I I I I I

Power steering fluid & lines* I I I I I I I I

Drive shaft boots I I I I I I I I I I I I I I I I I

Seat belts, buckles & anchors I I I I I I I I I I I I I I I I I

Lubricate locks, hinges & hoodlatch

I I I I I I I I

Chart Symbols:I – Inspect these items and their related parts. If necessary, correct, clean, replenish, adjust or replace.R – Replace or change.(2) More frequent maintenance is required if driving under dusty conditions.(3) Refer to”Recommended Fluids And Lubricants.”(5) Change the brake/clutch fluid every 9,000 miles (14,400 kilometers) or 9months, whichever comes first, if the vehicleis operated under any of the following conditions :

– Driving in hilly or mountainous terrain.

(6) More frequent maintenance is required if the vehicle is operated under any of the following conditions:– Short–distance driving.– Extensive idling or slow–speed driving in stop–and–go traffic.– Driving on dusty roads.

(7) Change the automatic transaxle fluid every 50,000miles (80,000 kilometers) if the vehicle is operated under any of thefollowing conditions :

– Driving in hilly or mountainous terrain.– Driving in heavy city traffic where the outside temperatures regularly reach 32³C (90³F) or higher.– Driving a taxi, or police or delivery vehicles.

(8) If necessary, rotate and balance the wheelsNote : Check the engine oil and radiator coolant levels ev-ery week.

0B – 12IGENERAL INFORMATION

DAEWOO V–121 BL4

* Replacement or inspection of these emissions components is recommended to be performed at the indicated intervalshowever, the California Air Resources Board has determined that performing thesemaintenance items are not requiredto maintained your vehicle emission warranty.

OWNER INSPECTIONS ANDSERVICES

WHILE OPERATING THE VEHICLE

Horn OperationBlow the horn occasionally to make sure it works. Checkall the button locations.

Brake System OperationBe alert for abnormal sounds, increased brake pedal trav-el, or repeated pulling to one side when braking. Also, if thebrake warning light goes on or flashes, something may bewrong with part of the brake system.

Exhaust System OperationBe alert to any changes in the sound of the system or thesmell of the fumes. These are signs that the system maybe leaking or overheating. Have the system inspected andrepaired immediately.

Tires,Wheels and Alignment OperationBe alert to any vibration of the steering wheel or the seatsat normal highway speeds. This may mean a wheel needsto be balanced. Also, a pull to the right or the left on astraight, level road may show the need for a tire pressureadjustment or a wheel alignment.

Steering System OperationBe alert to changes in the steering action. An inspectionis needed when the steering wheel is hard to turn, has toomuch free play, or if unusual sounds are noticed whenturning or parking.

Headlamp AimTake note of the light pattern occasionally. Adjust theheadlamps if the beams seem improperly aimed.

AT EACH FUEL FILLA fluid loss in any (except windshield washer) system mayindicate a problem. Have the system inspected and re-paired immediately.

Engine Oil LevelCheck the oil level and add oil, if necessary. The best timeto check the engine oil level is when the oil is warm.

1. After stopping the engine, wait a few minutes forthe oil to drain back to the oil pan.

2. Pull out the oil level indicator (dipstick).3. Wipe it clean, and push the oil level indicator back

down all the way.4. Pull out the oil level indicator and look at the oil lev-

el on it.

5. Add oil, if needed, to keep the oil level above theMIN line and within the area labeled ”OperatingRange.” Avoid overfilling the engine, since this maycause engine damage.

6. Push the indicator all the way back down into theengine after taking the reading.

If checking the oil level when the oil is cold, do not run theengine first. The cold oil will not drain back to the pan fastenough to give a true oil level reading.

Engine Coolant Level and ConditionCheck the coolant level in the coolant reservoir tank andadd coolant, if necessary. Inspect the coolant. Replacedirty or rusty coolant.

Windshield Washer Fluid LevelCheck the washer fluid level in the reservoir. Add fluid, ifnecessary.

AT LEAST MONTHLYTire and Wheel Inspection and PressureCheckCheck the tires for abnormal wear or damage. Also, checkfor damaged wheels. Check the tire pressure when thetires are cold (check the spare tire, unless it is a stow-away). Maintain the recommended pressures that are onthe tire placard that is on the driver’s side door.

Lamp OperationCheck the operation of the license plate lamp, the head-lamps (including the high beams), the parking lamps, thefog lamps, the taillamp, the brake lamps, the turn signals,the backup lamps, and the hazardwarning flasher.

Fluid Leak CheckPeriodically inspect the surface beneath the vehicle forwater, oil, fuel or other fluids, after the vehicle has beenparked for a while. Water dripping from the air conditioningsystem after use is normal. If you notice fuel leaks orfumes, find the cause and correct it immediately.

AT LEAST TWICE A YEAR

Power Steering System Reservoir LevelCheck the power steering fluid level. Keep the powersteering fluid at the proper level. Refer to Section 6A, Pow-er Steering System.

Brake Master Cylinder Reservoir LevelCheck the fluid and keep it at the proper level. A low fluidlevel can indicate worn disc brake pads andmay need tobe serviced. Check the breather hole in the reservoir coverthat it is free from dirt and check for an open passage.

Clutch Pedal Free TravelCheck clutch pedal free travel and adjust, as necessary,every 16,000 km (10,000 miles). Measure the distancefrom the center of the clutch pedal to the outer edge of the

GENERAL INFORMATION 0B – 13

DAEWOO V–121 BL4

steering wheel with the clutch pedal not pressed. Then,measure the distance from the center of the clutch pedalto the outer edge of the steering wheel with the clutch ped-al fully pressed. The difference between the two valuesmust be greater than 130 mm (5.1 in.).

Weatherstrip LubricationApply a thin film of silicone grease using a clean cloth.

EACH TIME THE OIL IS CHANGED

Automatic Transaxle FluidRefer to”Transaxle Fluid Level Checking Procedure”in-Section 5A, 4T40E Automatic Transaxle.

Manual TransaxleCheck the fluid level and add fluid, as required. RefertoSection 5B, Five–Speed Manual Transaxle.

Brake System InspectionThis inspection should be done when the wheels are re-moved for rotation. Inspect the lines and the hoses forproper hookup, binding, leaks, cracks, chafing, etc. In-spect the disc brake pads for wear. Inspect the rotors forsurface condition. Also, inspect the drum brake linings forwear and cracks. Inspect other brake parts, including thedrums, the wheels cylinders, the parking brake, etc., at thesame time. Check the parking brake adjustment. Inspectthe brakes more often if habit or conditions result in fre-quent braking.

Steering, Suspension and Front Drive AxleBoot and Seal InspectionInspect the front and the rear suspension and the steeringsystem for damaged, loose, or missing parts; signs ofwear; or lack of lubrication. Inspect the power steeringlines and the hoses for proper hookup, binding, leaks,cracks and chafing, etc. Clean and inspect the drive axleboot and seals for damage, tears, or leakage. Replace theseals, if necessary.

Exhaust System InspectionInspect the complete system (including the catalytic con-verter, if equipped). Inspect the body near the exhaustsystem. Look for broken, damaged, missing, or out ofposition parts, as well as open seams, holes, loose con-nections, or other conditions which could cause heat build-up in the floor pan or could let exhaust fumes seep into thetrunk or passenger compartment.

Throttle Linkage InspectionInspect the throttle linkage for interference or binding,damaged or missing parts. Lubricate all linkage joints andthrottle cable joints, the intermediate throttle shaft bearing,the return spring at the throttle valve assembly, and the ac-celerator pedal sliding face with suitable grease. Checkthe throttle cable for free movement.

Engine Drive BeltsInspect all belts for cracks, fraying, wear, and proper ten-sion. Adjust or replace the belts, as needed.

Hood Latch OperationWhen opening the hood, note the operation of the secon-dary latch. It should keep the hood from opening all theway when the primary latch is released. The hood mustclose firmly.

AT LEAST ANNUALLY

Lap and Shoulder Belt Condition andOperationInspect the belt system, including the webbing, thebuckles, the latch plates, the retractor, the guide loops andthe anchors.

Movable Head Restraint OperationOn vehicles with movable head restraints, the restraintsmust stay in the desired position.

Spare Tire and Jack StorageBe alert to rattles in the rear of the vehicle. The spare tire,all the jacking equipment, and the tools must be securelystowed at all times. Oil the jack ratchet or the screw mech-anism after each use.

Key Lock ServiceLubricate the key lock cylinder.

Body Lubrication ServiceLubricate all the body door hinges including the hood, thefuel door, the rear compartment hinges and the latches,the glove box and the console doors, and any folding seathardware.

Transaxle Neutral Switch Operation onAutomatic TransaxleCAUTION : Adhere to the following precautions. Fai-luretodosocancauseinjuriesandpropertydamage.

Firmly apply the parking brake and the regularbrakes.

Do not use the accelerator pedal. Be ready to turn the ignition OFF if the vehicle

starts.On automatic transaxle vehicles, try to start the engine ineach gear. The starter should crank only in P (PARK) andin N (NEUTRAL).

Parking Brake and Transaxle P (PARK)Mechanism OperationCAUTION : To reduce the risk of personal injury orproperty damage, be prepared to apply the regularbrakes if the vehicle begins to move.Park on a fairly steep hillwith enough roomformovementin the downhill direction. To check the parking brake, withthe engine running and the transaxle in N (NEUTRAL),slowly remove foot pressure fromthe regular brake pedal(until only the parking brake is holding the vehicle).To check the automatic transaxle P (PARK) mechanism’sholding ability, release all brakes after shifting the trans-axle to P (PARK).

0B – 14IGENERAL INFORMATION

DAEWOO V–121 BL4

Underbody FlushingFlushing the underbody will remove any corrosive materi-als used for ice and snow removal and dust control. Atleast every spring, clean the underbody. First, loosen thesediment packed in closed areas of the vehicle. Then,flush the underbodywith plainwater.

Engine Cooling SystemInspect the coolant and freeze protection fluid. If the fluid

is dirty or rusty, drain, flush and refill the engine coolingsystem with new coolant. Keep the coolant at the propermixture to ensure proper freeze protection, corrosionprotection and engine operating temperature. Inspect thehoses. Replace the cracked, swollen, or deterioratedhoses. Tighten the clamps. Clean the outside of the radia-tor and the air conditioning condenser. Wash the filler capand the neck. Pressure test the cooling system and thecap to help ensure proper operation.

GENERAL INFORMATION 0B – 15

DAEWOO V–121 BL4

RECOMMENDED FLUIDS AND LUBRICANTS

USAGE CAPACITY FLUID/LUBRICANT

Engine Oil 3.8L (4.1 qt) ILSAC GF–II (API SJ) gradeSAE 5W––30, SAE 10W––30

Engine Coolant 7.0L (7.4 qt) Mixture of water and good quality ethylene glycol–base antifreeze (year–round coolant)

Brake and Clutch Fluid 0.5L (0.5 qt) SSK–221 (DOT–3 and DOT–4 Fluid)

Power Steering System Fluid 1.0L (1.1 qt) DEXRON±–III, DEXRON± II–D

Automatic Transaxle 11.5L (12.2 qt) DEXRON±–III

Manual Transaxle 1.8L (2 qt) Manual Transaxle Fluid ( B0400075, SAE80 or eqi-valent; Extremely cold area: SAE 75W)

Manual Transaxle Shift Linkage As needed Multipurpose–type grease meeting requirementsNLGI No. 1 or 2

Key Lock Cylinders As needed Silicone lubricant

Automatic Transaxle Shift Link-age

As needed Engine oil

Clutch Linkage Pivot Points As needed Engine oil

Floor Shift Linkage Points As needed Engine oil

Hood Latch Assembly

1. Pivots and Spring Anchor2. Release Pawl

As needed 1. Engine oil2. Multipurpose–type grease meeting require-

ments NLGI No. 1 or 2

Hood and door hingesFuel door hingeRear compartment lid hinges

As needed Engine oil

Weatherstripping As needed Silicone grease

0B – 16IGENERAL INFORMATION

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

GENERAL REPAIR INSTRUCTIONSIf a floor jack is used, the following precautions are recom-mended: Park the vehicle on level ground, ”block” the front or

rear wheels, set the jack against the frame, raisethe vehicle and support it with chassis stands, andthen perform the service operation.

Before performing the service operation, disconnectthe negative battery cable to reduce the chance ofcable damage and burning due to short–circuiting.

Use a cover on the body, the seats, and the floor toprotect them against damage and contamination.

Handle brake fluid and antifreeze solution with careas they can cause paint damage.

The use of proper tools, and the required specialtools where specified, is important for efficient andreliable performance of the service repairs.

Use genuine DAEWOO parts. Discard used cotter pins, gaskets, O–rings, oil

seals, lock washers and self–locking nuts. Preparenew ones for installation. Normal functioning of thevehicle’s components cannot be maintained if thesefasteners and seals are reused.

Keep the disassembled parts to assist in reassemb-ly.

Keep attaching bolts and nuts separated, as theyvary in hardness and design depending on the posi-tion of the installation.

Clean the parts before inspection or reassembly. Clean the oil parts, etc. Use compressed air to

make certain they are free of restrictions. Lubricate rotating and sliding faces of parts with oil

or grease before installation. When necessary, use a sealer on gaskets to pre-

vent leakage. Carefully observe all specifications for bolt and nut

torques.When service operation is complete, make a final checkto be sure service was done properly and the problem wascorrected.

GENERAL INFORMATION 0B – 17

DAEWOO V–121 BL4

GENERAL DESCRIPTION

ON BOARD REFUELING VAPORRECOVERY SYSTEMThe NUBIRA 2.0 DOHC model is equipped with an OnBoard Diagnostic Stage II (OBD–II) system to meet en-hanced emission control requirements. Within this OBD–IIsystem, an On Board Refueling Vapor Recorvery (ORVR)system has been developed and equipped to meet en-hanced evaporative emission control requirements duringvehicle moving, parking, and refueling at gas stations. TheDaewoo ORVR system adopts one canister to collect bothevaporative vapors during the moving & parking as well asrefueling vapor. Collected vapor is consurmed by the en-gine through the intake manfold during vehicle operation.The mechanism of Daewoo ORVR system to meet theORVR requirement is to create suction inside filler neck bythe aid of fuel flow through a reduced diameter section inthe filler pipe.Therefore, Daewoo ORVR system adopts the so called”Liquid Trap” or ”Liquid Seal” system that assures the longterm durability.The Daewoo ORVR system provides nozzle compatibilitywith conventional and stage II vapor recovery nozzle.

The Daewoo ORVR system has been designed to havethe following functional features. To collect refueling vapors and to route to canister. To provide nozzle compatibility with conventional

and stage II vapor recovery nozzles. To provide fill shut off signal. To prevent canister from liquid fuel during normal

driving and vehicle rollover. To provide fuel tank venting to canister during ve-

hicle operation. To protect fuel tank from over–pressure. To protect fuel vapor dome from overfill.Any failures or malfunction of the ORVR system will beidentified by OBD–II system and warned through Malfunc-tion Indicator Lamp (MIL) on the instrument cluster.No special refueling procedures and mainternance onORVR system are required.The Daewoo ORVR system and all fuel system compo-nents have been designed to prevent the electrostatic dis-charge phenomenon by adopting mitigation techniquesrecommended in SAE J1645. Daewoo’s own test proce-dure (EDS–T–5005) is similar to SAE J1113.

0B – 18IGENERAL INFORMATION

DAEWOO V–121 BL4

Schematic Of On Board Refueling Vapor Recovery System

1. Manifold (Intake)2. Canister Purge Valve (Electronic Pwm Control)3. Service Port4. Integrated Fuel Vapor Storage Canister5. OBD–II Valve (Solenoid)OBD–II Valve (Solenoid)6. Air Filter7. Fuel Tank (Steel)8. Fuel Fill Vent Control Valve & Liquid–Vapor Dis-

criminator9. Pressure Relief Valve10. Tank Pressure Transducer (OBD–II)11. Rollover Valve12. 2–Way Check Valve13. Check Valve14. Fuel Filler Tube (Dynamic Seal During Fill)15. Fuel Filler Cap (Pressure–Vacuum Relief)

GENERAL INFORMATION 0B – 19

DAEWOO V–121 BL4

Component Locator

1. Fuel Tank2. Filler Tube3. Canister4. OBD– II Valve5. Fuel Filter

6. Purge Valve7. Service port8. Fuel Filler Cap9. Air Filter

0B – 20IGENERAL INFORMATION

DAEWOO V–121 BL4

VEHICLE IDENTIFICATION

Passenger Car VIN

Certification plate 1. Production Date2. Gross Vehicle Weight Rating3. Gross Axle Weight Rating Front4. Gross Axle Weight Rating Rear5. Vehicle Identification Number

GENERAL INFORMATION 0B – 21

DAEWOO V–121 BL4

VIN Plate LocationThe vehicle identification number (VIN) plate is attachedto the top of the driver’s side of the instrument panel.

Certification LabelThe Certification Label is attached to the driver’s side B–pillar near door strike.

Engraved VIN Location

The vehicle identification number (VIN) is engraved in thetop of the bulkhead, next to the ABS module.

0B – 22IGENERAL INFORMATION

DAEWOO V–121 BL4

Engine Number – Family II (2.0L DOHC Engine)

Engine Number Plate Location – Family II(2.0L DOHC Engine)

The engine number is stamped on the cylinder block underthe No. 4 exhaust manifold of the engine.

GENERAL INFORMATION 0B – 23

DAEWOO V–121 BL4

Manual Transaxle Identification NumberPlate

1. Identification Code2. Sequential Number

IdentificationCode

Engine Gear Ratio

FE 2.0L DOHC 3.545 C/R

Manual Transaxle Identification NumberPlate Location

The manual transaxle identification number is attached tothe top of the transaxle case near the engine.

Automatic Transaxle Identification NumberPlate

1. Assembly Plant (Windsor, Canada)2. Model Year (1996)3. Broadcast Code4. Model Name (4T40E)5. Update Level6. Sequential Number7. Manufacturer8. Part Number

Identification Code Engine

7ZZR 2.0L DOHC

0B – 24IGENERAL INFORMATION

DAEWOO V–121 BL4

Automatic Transaxle Identification NumberPlate Location

The automatic transaxle identification number plate is at-tached on the rear side of the transaxle near the bulkhead.

VEHICLE LIFTING PROCEDURESNotice : To raise the vehicle, place the lifting equipmentonly at the points indicated. Failure to use these precisepositions may result in permanent body deformation.Many dealer service facilities and service stations areequipped with automotive hoists that bear upon someparts of the frame to lift the vehicle. If any other hoist meth-od is used, use special care to avoid damaging the fueltank, the filler neck, the exhaust system, or the underbody.

GENERAL INFORMATION 0B – 25

DAEWOO V–121 BL4

0B – 26IGENERAL INFORMATION

DAEWOO V–121 BL4

Vehicle Lifting Points

SECTION : 1A

GENERAL ENGINE INFORMATION

TABLE OF CONTENTSDIAGNOSIS 1A–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

COMPRESSION TEST 1A–1. . . . . . . . . . . . . . . . . . . . .

OIL PRESSURE TEST 1A–2. . . . . . . . . . . . . . . . . . . . .

OIL LEAK DIAGNOSIS 1A–3. . . . . . . . . . . . . . . . . . . . .

KNOCK DIAGNOSIS 1A–4. . . . . . . . . . . . . . . . . . . . . . .

NOISE DIAGNOSIS 1A–8. . . . . . . . . . . . . . . . . . . . . . .

GENERAL INFORMATION 1A–11. . . . . . . . . . . . . . . . . .

CLEANLINESS AND CARE 1A–11. . . . . . . . . . . . . . . .

ON–ENGINE SERVICE 1A–11. . . . . . . . . . . . . . . . . . .

DIAGNOSIS

COMPRESSION TESTImportant : Disconnect the Crankshaft Position Sensor(CPS) connector to disable the fuel and the ignition sys-tems.

Test the compression pressure for each cylinder. Lowcompression pressure may be the fault of the valves or thepistons. The following conditions should be consideredwhen checking the cylinder compression:

The engine should be at normal operating tempera-ture.

The throttle must be wide open. All the spark plugs should be removed. The battery must be at or near full charge.

1. Place approximately three squirts of oil from aplunger type oiler into each spark plug port.

2. Insert the engine compression gauge into eachspark plug port.

3. Crank test each cylinder with four to five compres-sion strokes using the starter motor.

4. The lowest reading should not be less than 70% ofthe highest reading. The compression gauge read-ing should not be less than 689 kPa (100 psi) forany of the cylinders.

5. Examine the gauge readings obtained after the four”puffs” per cylinder are obtained from cranking thestarter motor. The readings are explained in thefollowing descriptions:

Normal Condition – Compression builds up quicklyand evenly to specified compression on each cylin-der.

Piston Rings Faulty – Compression is low on thefirst stroke and tends to build up on followingstrokes, but does not reach normal. The compres-sion pressure improves considerably with the addi-tion of oil into the cylinder.

Valves Faulty – Low compression pressure on thefirst stroke. The compression pressure does nottend to build up on the following strokes. The com-pression pressure does not improve much with theaddition of oil into the cylinder.

1A – 2IGENERAL ENGINE INFORMATION

DAEWOO V–121 BL4

OIL PRESSURE TEST

Step Action Value(s) Yes No

1 Is the oil pressure warning lamp on? Go to Step 2 System OK

2 Check the oil level in the crankcase.Is the oil level low?

Go to Step 3 Go to Step 4

3 Add oil so that the oil level is up to the MAX mark onthe indicator.Is the repair complete?

Go to Step 1

4 Check the idle speed.Is the idle speed below the value specified?

825 rpm Go to Step 5 Go to Step 6

5 Increase the idle speed.Is the speed increased?

Go to Step 1

6 Inspect the oil pressure switch.Is the oil pressure switch incorrect or malfunction-ing?

Go to Step 7 Go to Step 8

7 Install a new oil pressure switch.Is the repair complete?

Go to Step 1

8 Inspect the oil pressure gauge.Is the oil pressure gauge incorrect or malfunction-ing?

Go to Step 9 Go to Step 10

9 Install a new oil pressure gauge.Is the repair complete?

Go to Step 1

10 Inspect the engine oil.Is the engine oil in the crankcase diluted or of the im-proper viscosity?

Go to Step 11 Go to Step 12

11 Install new engine oil of the proper viscosity for theexpected temperatures.Is the repair complete?

Go to Step 1

12 Inspect the oil pump.Is the pump worn or dirty?

Go to Step 13 Go to Step 14

13 Replace the oil pump.Is the repair complete?

Go to Step 1

14 Inspect the oil filter.Is the oil filter plugged?

Go to Step 15 Go to Step 16

15 Install a new oil filter.Is the repair complete?

Go to Step 1

16 Inspect the oil pickup screen.Is the oil pickup screen loose or plugged?

Go to Step 17 Go to Step 18

17 Tighten or replace the oil pickup screen as neces-sary.Is the repair complete?

Go to Step 1

18 Inspect the oil pickup tube.Are there any holes in the oil pickup tube?

Go to Step 19 Go to Step 20

19 Replace the oil pickup tube.Is the repair complete?

Go to Step 1

GENERAL ENGINE INFORMATION 1A – 3

DAEWOO V–121 BL4

Step NoYesValue(s)Action

20 Inspect the bearing clearances.Are the bearing clearances more than the valuesspecified?

Crankshaft0.005 mm

(0.0001 in.)Connecting

Rod0.0019–0.070

mm(0.0007–0.0025

in.)

Go to Step 21 Go to Step 22

21 Replace the bearing, if necessary.Is the repair complete?

Go to Step 1

22 Inspect the oil galleries.Are the oil galleries cracked, porous, or plugged?

Go to Step 23 Go to Step 24

23 Repair or replace the engine block.Is the repair complete?

Go to Step 1

24 Inspect the gallery plugs.Are any of the gallery plugs missing or installed im-properly?

Go to Step 25 Go to Step 26

25 Install plugs or repair, as necessary.Is the repair complete?

Go to Step 1

26 Inspect the camshaft.Is the camshaft worn or is there evidence of poormachining?

Go to Step 27 System OK

27 Replace the camshaft.Is the repair complete?

Go to Step 1

OIL LEAK DIAGNOSISMost fluid oil leaks are easily located and repaired by visu-ally finding the leak and replacing or repairing the neces-sary parts. On some occasions, a fluid leak may be difficultto locate or repair. The following procedures may help youin locating and repairing most leaks.

Finding the Leak:1. Identify the fluid. Determine whether it is engine

oil,automatic transmission fluid, power steeringfluid, etc.

2. Identify where the fluid is leaking from.

1) After running the vehicle at normal operatingtemperature, park the vehicle over a large sheetof paper.

2) Wait a few minutes.3) You should be able to find the approximate loca-

tion of the leak by the drippings on the paper.

3. Visually check around the suspected component.Check around all the gasket mating surfaces forleaks. A mirror is useful for finding leaks in areasthat are hard to reach.

4. If the leak still cannot be found, it may be neces-sary to clean the suspected area with a degreaser,steam or spray solvent.

1) Thoroughly clean the area.2) Dry the area.3) Operate the vehicle for several miles at normal

operating temperature and varying speeds.4) After operating the vehicle, visually check the

suspected component.5) If you still cannot locate the leak, try using the

powder or black light and dye method.

Powder Method:1. Clean the suspected area.2. Apply an aerosol–type powder (such as foot pow-

der) to the suspected area.3. Operate the vehicle under normal operating condi-

tions.4. Visually inspect the suspected component. You

should be able to trace the leak path over the whitepowder surface to the source.

Black Light and Dye Method:A dye and light kit is available for finding leaks. Refer to themanufacturer’s directions when using the kit.

1. Pour the specified amount of dye into the engine oilfill tube.

1A – 4IGENERAL ENGINE INFORMATION

DAEWOO V–121 BL4

2. Operate the vehicle under normal operating condi-tions as directed in the kit.

3. Direct the light toward the suspected area. Thedyed fluid will appear as a yellow path leading tothe source.

Repairing the Leak:Once the origin of the leak has been pinpointed and tracedback to its source, the cause of the leak must be deter-mined in order for it to be repaired properly. If a gasket isreplaced, but the sealing flange is bent, the new gasket willnot repair the leak. The bent flange must be repaired also.Before attempting to repair a leak, check for the followingconditions and correct them as they may cause a leak.

Gaskets: The fluid level/pressure is too high. The crankcase ventilation system is malfunctioning. The fasteners are tightened improperly or the

threads are dirty or damaged.

The flanges or the sealing surface is warped. There are scratches, burrs or other damage to the

sealing surface. The gasket is damaged or worn. There is cracking or porosity of the component. An improper seal was used, (where applicable).

Seals:

The fluid level/pressure is too high. The crankcase ventilation system is malfunctioning. The seal bore is damaged (scratched, burred or

nicked). The seal is damaged or worn. Improper installation is evident. There are cracks in the component. The shaft surface is scratched, nicked or damaged. A loose or worn bearing is causing excess seal

wear.

KNOCK DIAGNOSISDefinition for KnockEngine knock refers to the various types of engine noise.Heavy knock is usually very loud and the result of brokenor excessively worn internal engine components. Light

knock is a noticeable noise, but not as loud. Light knockcan be caused by worn internal engine components.Loose or broken external engine components can alsocause heavy or light knock.

Engine Knocks Cold and Continues for Two–Three Minutes and/orKnock Increases with Engine Torque

Step Action Value(s) Yes No

1 Does the engine knock when it is cold and continuefor two to three minutes or does the knock increasewith torque?

Go to Step 2 System OK

2 Inspect the flywheel.Is the flywheel contacting the splash shield?

Go to Step 3 Go to Step 4

3 Reposition the splash shield.Is the repair complete?

Go to Step 1

4 Inspect the balancer and the drive pulleys.Is either the balancer or the drive pulleys loose orbroken?

Go to Step 5 Go to Step 6

5 Tighten or replace the balancer or the drive pulleys.Is the repair complete?

Go to Step 1

6 Inspect the piston–to–bore clearance.Is the clearance more than the value specified?

0.030 mm(0.001 in.)

Go to Step 7 Go to Step 8

7 1. Rebore the cylinder and hone to size.2. Replace the piston.Is the repair complete?*

Go to Step 1

8 Inspect the connecting rod.Is the connecting rod bent?

Go to Step 9 System OK

9 Replace the connecting rod.Is the repair complete?

Go to Step 1

* Cold engine piston knock usually disappears when the cylinder is grounded out. Cold engine piston knock, which disap-pears in about 1.5 minutes, is considered acceptable.

GENERAL ENGINE INFORMATION 1A – 5

DAEWOO V–121 BL4

Heavy Knock Hot with Torque Applied

Step Action Value(s) Yes No

1 Is there a heavy knock when the engine is hot andtorque is applied?

Go to Step 2 System OK

2 Inspect the balancer and the pulley hub.Is the balancer or the pulley hub broken?

Go to Step 3 Go to Step 4

3 Replace the broken balancer or the pulley hub.Is the repair complete?

Go to Step 1

4 Inspect the torque converter bolts.Are the bolts tightened to specified value?

45Nm(33 lb–ft)

Go to Step 5 Go to Step 6

5 Tighten the torque converter bolts.Is the repair complete?

Go to Step 1

6 Inspect the accessory belts.Are the belts too tight or nicked?

Go to Step 7 Step 8

7 Replace and/or tension the belts to specifications asnecessary.Is the repair complete?

Go to Step 1

8 Inspect the exhaust system.Is the system grounded?

Go to Step 9 Go to Step 10

9 Reposition the system as necessary.Is the repair complete?

Go to Step 1

10 Inspect the flywheel.Is the flywheel cracked?

Go to Step 11 Go to Step 12

11 Replace the flywheel.Is the repair complete?

Go to Step 1

12 Inspect the main bearing clearance.Is the clearance more than the specified value?

2.0 DOHC0.015–0.040

mm(0.00059–0.001

5 in.)

Go to Step 13 Go to Step 14

13 Replace the main bearings as necessary.Is the repair complete?

Go to Step 1

14 Inspect the rod bearing clearance.Is the clearance more than the specified value?

0.019–0.070mm

(0.0007–0.0027in.)

Go to Step 15 System OK

15 Replace the rod bearings as necessary.Is the repair complete?

Go toStep 1

1A – 6IGENERAL ENGINE INFORMATION

DAEWOO V–121 BL4

Light Knock Hot

Step Action Value(s) Yes No

1 Is there a light knock when the engine is hot? Go to Step 2 System OK

2 Is detonation or spark knock evident? Go to Step 3 Go to Step 4

3 Check the engine timing and the fuel quality.Was the problem found?

Go to Step 1

4 Inspect the torque converter bolts.Are the bolts loose?

45 Nm (33 lb–ft)

Go to Step 5 Go to Step 6

5 Tighten the torque converter bolts.Is the repair complete?

Go to Step 1

6 Inspect the manifold.Is there an exhaust leak at the manifold?

Go to Step 7 Go to Step 8

7 Tighten the bolts or replace the gasket.Is the repair complete?

Go to Step 1

8 Check the rod bearing clearance.Is the clearance within the specified value?

0.019–0.070mm

(0.0007–0.0027in.)

Go to Step 9 System OK

9 Replace the rod bearings as necessary.Is the repair complete?

Go to Step 1

Knocks During Initial Start–Up But Lasts Only a Few Seconds

Step Action Value(s) Yes No

1 Does the engine knock during initial start–up but lastonly a few seconds?

Go to Step 2 System OK

2 Check the engine oil.Is the proper viscosity oil used in the crankcase?

Go to Step 4 Go to Step 3

3 Install oil of the proper viscosity for the expectedseasonal temperatures.Is the repair complete?

Go to Step 1

4 Inspect the hydraulic lifters.Is there evidence of hydraulic lifter bleed–down?

Go to Step 5 Go to Step 6

5 Clean, test and replace the lifters as necessary.Is the repair complete?*

Go to Step 1

6 Inspect the crankshaft end clearance.Is the clearance more than specified value?

0.01 mm(0.0039 in.)

Go to Step 7 Go to Step 8

7 Replace the crankshaft thrust bearing.Is the repair complete?

Go to Step 1

8 Inspect the front main bearing clearance.Is the clearance more than the specified value?

2.0 DOHC0.015–0.040

mm(0.00059–0.001

5 in.)

Go to Step 9 System OK

9 Replace the worn parts of the front main bearing.Is the repair complete?

Go to Step 1

* When the engine is stopped, some valves will be open. Spring pressure against the lifters will tend to bleed the lifter down.Attempts to repair this should be made only if the problem is consistent.

An engine that is only operated for short periods between start–ups may have lifter noise that lasts for a few minutes. Thisis a normal condition.

GENERAL ENGINE INFORMATION 1A – 7

DAEWOO V–121 BL4

Knocks at Idle Hot

Step Action Value(s) Yes No

1 Does the engine knock at idle when hot? Go to Step 2 System OK

2 Inspect the drive belts.Are the belts loose or worn?

Go to Step 3 Go to Step 4

3 Tension or replace the belts as necessary.Is the repair complete?

Go to Step 1

4 Inspect the A/C compressor and the generator.Is either the compressor or the generator faulty?

Go to Step 5 Go to Step 6

5 Replace the faulty A/C compressor or the generator.Is the repair complete?

Go to Step 1

6 Inspect the valve train.Are valve train components faulty?

Go to Step 7 Go to Step 8

7 Replace the faulty valve train components.Is the repair complete?

Go to Step 1

8 Check the engine oil.Is the proper viscosity oil used in the crankcase?

Go to Step 10 Go to Step 9

9 Install oil of the proper viscosity for the expectedseasonal temperatures.Is the repair complete?

Go to Step 1

10 Inspect the piston pin clearance.Is the clearance more than the specified value?

2.0L DOHC0.014 mm

(0.0005 in.)

Go to Step 11 Go to Step 12

11 Replace the piston and the pin.Is the repair complete?

Go to Step 1

12 Check the connecting rod alignment.Is the alignment faulty?

Go to Step 13 Go to Step 14

13 Check and replace rods as necessary.Is the repair complete?

Go to Step 1

14 Inspect the piston–to–bore clearance.Is the clearance within the specified value?

0.03 mm(0.0012 in.)

Go to Step 16 Go to Step 15

15 Hone the bore and fit a new piston.Is the repair complete?

Go to Step 1

16 Inspect the crankshaft balancer.Is the balancer loose?

Go to Step 17 Go to Step 18

17 Torque or replace worn parts.Is the repair complete?

Go to Step 1

18 Check the piston pin offset.Is the offset at the specified value?

0.5–0.7 mm(0.019–0.027

in.)Toward Thrust

Side

Go to Step 19 System OK

19 Install the correct piston.Is the repair complete?

Go to Step 1

1A – 8IGENERAL ENGINE INFORMATION

DAEWOO V–121 BL4

NOISE DIAGNOSIS

Main Bearing Noise

Step Action Value(s) Yes No

1 Are dull thuds or knocks heard with every enginerevolution?

Go to Step 2 System OK

2 Check the oil pump pressure.Is the oil pump pressure low?

Go toOil Pres-sure Test

Go to Step 3

3 Inspect the crankshaft end play.Is there excessive crankshaft end play?

0.1 mm(0.0039 in.)

Go toCrank-shaft Replace-ment Proce-

dure

Go to Step 4

4 Inspect the crankshaft journals.Are the crankshaft journals out–of–round?

0.004 mm(maximum)(0.0006 in.)

Go toCrank-shaft Replace-ment Proce-

dure

Go to Step 5

5 Inspect the belt tension.Is there excessive belt tension?

Go toTimingBelt Replace-ment Proce-

dure

Go to Step 6

6 Inspect the crankshaft pulley.Is the crankshaft pulley loose?

Go toCrank-shaft Replace-ment Proce-

dure

System OK

Connecting Rod Bearing Noise Symptom

Step Action Value(s) Yes No

1 Is a knock noise heard under all engine speeds? Go to Step 2 System OK

2 Inspect the crankshaft connecting rod journal.Is the crankshaft connecting rod journal worn?

Go toCrank-shaft Replace-ment Proce-

dure

Go to Step 3

3 Check the oil pump pressure.Is the oil pump pressure low?

Go toOil Pres-sure Test

Go to Step 4

4 Inspect the crankshaft connecting rod journals.Are the journals out–of–round?

Go toCrank-shaft Replace-ment Proce-

dure

Go to Step 5

5 Inspect the connecting rods.Is there a misaligned connecting rod?

Go toPistonsand Rods Re-

placement Pro-cedure

Go to Step 6

6 Inspect the connecting rod bolts.Are the connecting rod bolts torqued properly?

System OK Go toPistonsand Rods Re-

placement Pro-cedure

GENERAL ENGINE INFORMATION 1A – 9

DAEWOO V–121 BL4

Piston Noises

Step Action Value(s) Yes No

1 Are any of the following noises heard: a sharp doubleknock when the engine is idling, a light ticking withno load on the engine, or a ”slapping” noise when theengine is cold?

Go to Step 2 System OK

2 Inspect the piston pin and the bushing.Is the piston pin or the bushing worn or loose?

Go toPistonsand Rods Re-

placement Pro-cedure

Go to Step 3

3 Inspect the piston.Is the piston broken or cracked?

Go toPistonsand Rods Re-

placement Pro-cedure

Go to Step 4

4 Inspect the connecting rods.Is there a misaligned connecting rod?

Go toPistonsand Rods Re-

placement Pro-cedure

Go to Step 5

5 Inspect the piston position.Is the piston 180³ out of position?

Go toPistonsand Rods Re-

placement Pro-cedure

System OK

1A – 10IGENERAL ENGINE INFORMATION

DAEWOO V–121 BL4

Valve Mechanism or Valve Train Noises

Step Action Value(s) Yes No

1 Is a light tapping sound heard from the engine? Go to Step 2 System OK

2 Inspect the valve springs.Are the springs weak or broken?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

Go to Step 3

3 Inspect the valves.Are the valves sticking or warped?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

Go to Step 4

4 Inspect the valve lifters.Are the valve lifters dirty, stuck or worn?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

Go to Step 5

5 Inspect the camshaft lobes.Are the camshaft lobes damaged or improperly ma-chined?

Go toCamshaftReplacement

Procedure

Go to Step 6

6 Check the oil supply to the valve train.Is the oil supply insufficient or poor?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

Go to Step 7

7 Inspect the valve guides.Are the valve guides worn?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

Go to Step 8

8 Inspect the valve spring seat.Is the valve spring seat incorrect?

Go toCylinderHead and

Valve TrainComponentsReplacement

Procedure

System OK

GENERAL ENGINE INFORMATION 1A – 11

DAEWOO V–121 BL4

GENERAL INFORMATION

CLEANLINESS AND CAREAn automobile engine is a combination of many machined,honed, polished and lapped surfaces with tolerances thatare measured in ten–thousandths of an inch. When any in-ternal engine parts are serviced, care and cleanliness areimportant. A liberal coating of engine oil should be appliedto friction areas during assembly, to protect and lubricatethe surfaces on initial operation. Proper cleaning andprotection of machined surfaces and friction areas is partof the repair procedure. This is considered standard shoppractice even if not specifically stated.

Whenever valve train components are removed for ser-vice, they should be kept in order. They should be installedin the same locations and with the same mating surfaces,as when they were removed.

Battery cables should be disconnected before any major

work is performed on the engine. Failure to disconnectcables may result in damage to wire harness or other elec-trical parts.

ON–ENGINE SERVICECAUTION : Disconnect the negative battery cable be-fore removing or installing any electrical unit, orwhen a tool or equipment could easily come in con-tact with exposed electrical terminals. Disconnectingthis cable will help prevent personal injury and dam-age to the vehicle. The ignition must also be in LOCKunless otherwise noted.

Notice : Any time the air cleaner is removed, the intakeopening should be covered. This will protect against theaccidental entrance of foreign material, which could followthe intake passage into the cylinder and cause extensivedamage when the engine is started.

SECTION : 1C

DOHC ENGINE MECHANICALCAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a toolor equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will helpprevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

TABLE OF CONTENTSSPECIFICATIONS 1C–2. . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE SPECIFICATIONS 1C–2. . . . . . . . . . . . . . . . .

FASTENER TIGHTENING SPECIFICATIONS 1C–4. . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS 1C–6. . . . . . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS TABLE 1C–6. . . . . . . . . . . . . . . . . . .

COMPONENT LOCATOR 1C–8. . . . . . . . . . . . . . . . . . . .

UPPER END 1C–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LOWER END 1C–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE AND REPAIR 1C–12. . . . . . . . . . . . . .

ON–VEHICLE SERVICE 1C–12. . . . . . . . . . . . . . . . . . . .

VALVE COVER 1C–12. . . . . . . . . . . . . . . . . . . . . . . . . . .

CYLINDER HEAD AND GASKET 1C–14. . . . . . . . . . .

CAMSHAFTS 1C–24. . . . . . . . . . . . . . . . . . . . . . . . . . . .

TIMING BELT CHECK AND ADJUST 1C–27. . . . . . .

TIMING BELT 1C–31. . . . . . . . . . . . . . . . . . . . . . . . . . . .

OIL PAN 1C–36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OIL PUMP 1C–39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE MOUNT 1C–44. . . . . . . . . . . . . . . . . . . . . . . . .

INTAKE MANIFOLD 1C–46. . . . . . . . . . . . . . . . . . . . . .

EXHAUST MANIFOLD 1C–49. . . . . . . . . . . . . . . . . . . .

CAMSHAFT GEARS 1C–51. . . . . . . . . . . . . . . . . . . . . .

REAR TIMING BELT COVER 1C–53. . . . . . . . . . . . . .

ENGINE 1C–55. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PISTONS AND RODS 1C–63. . . . . . . . . . . . . . . . . . . .

UNIT REPAIR 1C–68. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CYLINDER HEAD AND VALVE TRAINCOMPONENTS 1C–68. . . . . . . . . . . . . . . . . . . . . . . .

CRANKSHAFT 1C–77. . . . . . . . . . . . . . . . . . . . . . . . . . .

CRANKSHAFT BEARINGS AND CONNECTING ROD BEARINGS – GAUGING PLASTIC 1C–88. . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CYLINDER HEAD AND GASKET 1C–91. . . . . . . . . . .

CRANKSHAFT 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . .

TIMING BELT 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . . .

OIL PUMP 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OIL PAN 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

EXHAUST MANIFOLD 1C–91. . . . . . . . . . . . . . . . . . . .

INTAKE MANIFOLD 1C–91. . . . . . . . . . . . . . . . . . . . . .

CAMSHAFTS 1C–91. . . . . . . . . . . . . . . . . . . . . . . . . . . .

1C – 2IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

SPECIFICATIONS

ENGINE SPECIFICATIONS

Application Description (Manual and Automatic)

General Data:

Engine Type 4–Cylinder (in–line)

Displacement 1,998 cm3 (121.92 in3)

Bore Stroke 86 x 86 mm (3.38 in. x 3.38 in.)

Compression Ratio 9.6 µ0.2 :1

Firing Order 1–3–4–2

Cylinder Bore:

Diameter 85.995~86.485 mm (3.3856~3.4049 in.)

Out of Round (Maximum) 0.013 mm (0.0005 in.)

Taper (Maximum) 0.013 mm (0.0005 in.)

Piston:

Diameter 85.955–86.485 mm (3.384–3.404 in.)

Clearance to Bore 0.0100~0.0300 mm (0.00039~0.00110 in.)

Piston Protrusion 0.5 mm (0.019 in.) Maximum

Piston Taper 0.013 mm (0.0005 in.)

Piston Rings:

Ring, End Gap, Top Compression 0.3~0.5 mm (0.011~0.019 in.)

Ring, End Gap, Second Compression 0.3~0.5 mm (0.011~0.019 in.)

Piston Pin:

Diameter 20.9970~20.9985 mm (0.82665~0.82671 in.)

Pin Offset 0.8 mm (0.03 in.) Toward Thrust Side

Clearance: In Piston 0.0035~0.0140 mm (0.00013~0.00055 in.)

Clearance: In Rod Interference Fit in Rod

Length 61.5 mm (2.42 in.)

Camshaft:

Lift – Intake 10.0 mm (0.39 in.)

Lift – Exhaust 10.0 mm (0.39 in.)

End Play 0.040~0.144 mm (0.0015~0.0056 in.)

Bearing Journal OD 42.455~43.470 mm (1.6714~1.7114 in.)

Crankshaft:

Main JournalDiameter (All)

57.974~57.995 mm (2.2824~2.2832 in.)

Out of Round (Maximum) 0.003 mm (0.0001 in.)

Main Bearing Clearance (All) 0.015–0.061 mm (0.00059~0.00239 in.)

Crankshaft End Play 0.070~0.302 mm (0.0027~0.0118 in.)

Service Oversize Available in 2 sizes0.25 mm and 9.50 mm (0.0098~0.0196 in.)

DOHC ENGINE MECHANICAL 1C – 3

DAEWOO V–121 BL4

Application Description (Manual and Automatic)

Connecting Rod Journal:Diameter (All)

48.981~ 48.987 mm (1.9283~1.9286 in.)

Out of Round (Maximum) 0.004 mm (0.00015 in.)

Rod Bearing Play 0.006~0.031 mm (0.00023~0.00122 in.)

Cylinder Head:

Valve Stem Protrusion 39.2~39.8 mm (1.54~1.56 in.)

Valve Guide Height 13.7–14.0 mm (0.54~0.57 in.)

Overall Height 134~0.025 mm (5.2755~0.0009 in.)

Minimum Overall Height After Machining 133.9 mm (5.27 in.)

Valve System:

Valve Lash Compensators Hydraulic

Seat Runout (Maximum, All) 0.03 mm (0.00118 in.)

Face Runout (Maximum, All) 0.03 mm (0.00118 in.)

Valve Stem DiameterIntake

6.998~7.012 mm (0.2755~0.2760 in.)

Exhaust 6.078~6.992 mm (0.2747~0.2752 in.)

Valve DiameterIntake

32µ0.1 mm (1.2598µ0.0039 in.)

Exhaust 29µ0.1 mm (1.1417µ0.0039 in.)

Valve Seat WidthIntake

1.0~1.5 mm (0.039~0.059 in.)

Exhaust 1.7~2.2 mm (0.066~0.086 in.)

Valve Face Angle 44³~40³

Valve Guide Inside Diameter 6.000~6.012 mm (0.236~0.237 in.)

Oil Pump:

Gear Lash 0.10~0.20 mm (0.003~0.007 in.)

Outer Gear to Body 0.11~0.19 mm (0.004~0.007 in.)

Outer Gear to Crescent 0.40~0.50 mm (0.015~0.019 in.)

Inner Gear to Crescent 0.35~0.40 mm (0.013~0.015 in.)

End Clearance 0.030~0.10 mm (0.001~0.003 in.)

Sealants and Adhesives:

Rear Main Bearing Cap GE p/n RTV 159

Camshaft Carrier to Cylinder Head HN 1581 (Loctite± 515)

Oil Pan Bolts HN 1256 (Loctite± 242)

Oil Pump Bolts HN 1256 (Loctite± 242)

Oil Pan Pickup Tube Bolts HN 1256 (Loctite± 242)

Oil Gallery Plug HN 1256 (Loctite± 242)

Coolant Jacket Caps and Plugs (Freeze Plugs) HN 1756 (Loctite± 176)

Exhaust Manifold Studs/Nuts Anti–seize Compound (HMC Spec HN1325)

1C – 4IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

FASTENER TIGHTENING SPECIFICATIONS

Application Nm Lb–Ft Lb–In

A/C Compressor Hose Assembly Bolt 33 24 –

Air Filter Housing Bolts 10 – 89

Automatic Tensioner Bolt 25 18 –

Auxiliary Catalytic Converter–to–Exhaust Manifold Nuts 40 30 –

Camshaft Bearing Cap Bolts, Intake and Exhaust 8 – 71

Camshaft Gear Bolt, Intake and Exhaust 50 + 60³+ 15³ 37 + 60³+ 15³ –

Camshaft Position Sensor Bolts 12 – 106

Connecting Rod Cap Bolts 36 + 45³+ 15³ 26 + 45³+ 15³ –

Coolant Bypass Housing and Mounting Bolts 15 11 –

Coolant Pump Retaining Bolts 25 18 –

Coolant Temperature Sensor 25 18 –

Crankshaft Bearing Cap Bolts 50 + 45³ + 15³ 37 + 45³ + 15³ –

Crankshaft Position Sensor Retaining Bolt 8 – 71

Crankshaft Pulley Bolts 20 15 –

Crankshaft Timing Belt Drive Gear Bolt 135+ 30³ +10³ 100+ 30³ +10³ –

Cylinder Head Bolts 25 + 90³ +90³+ 90³

18 + 90³ +90³+ 90³

–

EI System Ignition Coil and EGR Mounting Bracket Bolts 25 18 –

Engine Block Lower Support Bracket/Splash Shield Bolts 35 26 –

Engine Mount Bracket Retaining Bolts and Nuts 55 41 –

Engine Mount Bracket–to–Engine Mount Retaining Bolts 60 44 –

Engine Mount Retaining Bolts 60 44 –

Engine–to–Intake Manifold Support Bracket Bolts 20 15 –

Evaporative Emission Canister Purge Solenoid Bracket Bolt 5 – 44

Exhaust Gas Recirculation Valve Bolts 20 15 –

Exhaust Manifold Heat Shield Bolts 8 – 71

Exhaust Manifold Retaining Nuts 15 11 –

Exhaust Pipe Support Bracket Bolts 40 30 –

Flexible Plate Bolts 65 48 –

Flywheel Bolts 65 + 30³ + 15³ 48 + 30³ + 15³ –

Front Muffler Pipe–to–Main Catalytic Converter Nuts 30 22 –

Fuel Rail Retaining Bolts 25 18 –

Front Timing Belt Cover Bolts, Upper and Lower 6 – 53

Generator–to–Intake Manifold and Cylinder Head SupportBracket Bolts

37 27 –

Generator–to–Intake Manifold Strap Bracket Bolt, Upper andLower

22 16 –

Generator–to–Intake Manifold Support Bracket Bolts 35 26 –

Ignition Coil Mounting Bolts 10 – 89

Intake Manifold Retaining Nuts and Bolts 18 13 –

Intake Manifold Support Bracket Bolts 20 15 –

DOHC ENGINE MECHANICAL 1C – 5

DAEWOO V–121 BL4

Application Lb–InLb–FtNm

Lower Block Support Bracket Bolts 35 26 –

Oil Pan Drain Plug 35 26 –

Oil Pan Flange–to–Transaxle Retaining Bolts 40 30 –

Oil Pan Retaining Bolts 10 – 89

Oil Pressure Switch 40 30 –

Oil Pump Bolts 10 – 89

Oil Pump Rear Cover Bolts 6 – 53

Oil Pump/Pick–up Tube Bolts 10 – 89

Oil Pump Retaining Bolts 10 – 89

Pulse Pick–up Sensor Disc 13 – 115

Rear Timing Belt Cover Bolts 7 – 62

Safety Relief Valve Bolt 30 22 –

Spark Plug Cover Bolts 8 – 71

Spark Plugs 20 15 –

Support Bracket Bolts 40 30 –

Thermostat Housing Mounting Bolts 15 11 –

Throttle Cable Bracket Bolts 8 – 71

Timing Belt Automatic Tensioner Bolt 25 18 –

Timing Belt Idler Pulley Bolt 25 18 –

Timing Belt Idler Pulley Nut 25 18 –

Transmission/Transaxle Bell Housing Bolts 75 55 –

Transmission/Transaxle Torque Converter Bolts 60 44 –

Valve Cover Bolts 8 – 71

1C – 6IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

SPECIAL TOOLS

SPECIAL TOOLS TABLE

KM–653Adapter

KM–135Adapter

KM–805Valve Guide Reamer

J–36792Crankshaft Rear Oil Seal

Installer

MKM–571–BGauge

J–28467–BEngine Assembly Lift

Support

KM–412Engine Overhaul Stand

KM–348Spring Compressor

DOHC ENGINE MECHANICAL 1C – 7

DAEWOO V–121 BL4

KM–635Crankshaft Rear Oil Seal

Installer

KM–427Piston Pin Service Set

KM–340–0Cutter Set

Includes: KM–340–7Guide Drift

KM–340–13Cutters

KM–340–26Cutters

KM–470–BAngular Torque Gauge

KM–498–BPressure Gauge

1C – 8IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

COMPONENT LOCATOR

UPPER END

DOHC ENGINE MECHANICAL 1C – 9

DAEWOO V–121 BL4

1. Bolt2. Spark Plug Cover3. Oil Cap4. Oil Cap Seal5. Bolt6. Valve Cover7. Valve Cover Gasket8. Value Lash Adjuster9. Retainer10. Valve Cab11. Valve Spring12. Valve Stem Seal13. Valve Spring Seat14. Valve Guide15. Valve Spring Seat16. Exhaust Seat17. Intake Valve18. Exhaust Valve19. Bolt20. Front Bearing Cap21. Head Bolt22. Bolt23. Bearing Cap24. EGR Adapter25. EGR Adapter Gasket26. Cylinder Head

27. Exhaust Manifold Gasket28. Exhaust Manifold29. Nut30. Exhaust Manifold Heat Shield31. Cylinder Head Gasket32. Bolt33. Thermostat Housing34. Thermostat Housing Gasket35. Stud36. Sleeve37. Plug38. Bolt39. Camshaft Position Sensor40. Oil Gallery Plug41. Exhaust Camshaft42. Oil Seal Ring43. Camshaft Gear44. Washer45. Camshaft Gear Bolt46. Intake Camshaft47. Intake Manifold Gasket48. Intake Manifold49. Throttle Body Gasket50. Throttle Body51. Nut52. Exhaust Gas Recirculation Solenoid

1C – 10IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

LOWER END

DOHC ENGINE MECHANICAL 1C – 11

DAEWOO V–121 BL4

1. Connecting Rod2. Bearing3. Connecting Rod Bolt4. Piston Ring Set5. Piston Pin6. Piston7. Engine Block8. Sleeve9. Water Jacket Cap10. Bolt (Manual Transaxle)11. Flywheel (Manual Transaxle)12. Flexible Plate (Automatic Transaxle)13. Bolt (Automatic Transaxle)14. Clamp15. Hose16. Clamp17. Engine Vent Pipe18. Bolt19. Gasket20. Transaxle Input Shaft Bearing21. Rear Main Seal22. Crankshaft23. Ignition Transmitter Disk24. Bolt25. Splash Pan26. Oil Pan27. Drain Plug28. Seal Ring29. Bolt30. Sleeve31. Gasket32. Bolt33. Oil Pump Cover34. Ring Gear35. Gear36. Plug37. Washer38. Washer39. Bypass Valve Plug40. Special Screw41. Seal

42. Oil Filter43. Bypass Valve44. Pressure Relief Valve Plunger45. Pressure Relief Valve Spring46. Washer47. Pressure Relief Valve Plug48. Ring Seal49. Bolt50. Oil Suction Pipe51. Bolt52. Rear Timing Belt Cover53. Bolt54. Special Bolt55. Idler Pulley56. Stud57. Nut58. Bolt59. Tensioner60. Bolt61. Thrust Inner Washer62. Woodruff Key63. Crankshaft Gear64. Thrust Outer Washer65. Bolt66. Camshaft Drive Belt67. Seal68. Front Timing Belt Cover69. Bolt70. Bushing Plug71. Bushing72. Oil Gallery Plug73. Bolt74. Water Pump75. Seal Ring76. Crankshaft Revolution Sensor77. Bolt78. Knock Sensor79. Bolt80. Bolt

DOHC ENGINE MECHANICAL 1C – 91

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

CYLINDER HEAD AND GASKETThe cylinder head is made of an aluminum alloy and usescross–flow intake and exhaust ports. A spark plug is lo-cated in the center of each combustion chamber. The cyl-inder head houses the dual camshafts.

CRANKSHAFTThe crankshaft has eight integral weights which are castwith it for balancing. Oil holes run through the center of thecrankshaft to supply oil to the connecting rods, the bear-ings, the pistons, and the other components. The endthrust load is taken by the thrust washers installed at thecenter journal.

TIMING BELTThe timing belt coordinates and keeps the crankshaft andthe dual overhead camshafts synchronized. The timingbelt also turns the coolant pump. The timing belt and thepulleys are toothed so that there is no slippage betweenthem. There are two idler pulleys. An automatic tensionerpulley maintains the timing belt’s correct tension. The tim-ing belt is made of a tough reinforced rubber similar to thatused on the serpentine drive belt and requires no lubrica-tion.

OIL PUMPThe oil pump draws engine oil from the oil pan and feedsit under pressure to the various parts of the engine. An oilstrainer is mounted before the inlet of the oil pump to re-move impurities which could clog or damage the oil pumpor other engine components. When the crankshaft ro-tates, the oil pump driven gear rotates. This causes thespace between the gears to constantly open and narrow,pulling oil in from the oil pan when the space opens andpumping the oil out to the engine as it narrows.

At high engine speeds, the oil pump supplies a much high-er amount of oil than required for lubrication of the engine.The oil pressure regulator prevents too much oil from en-tering the engine lubrication passages. During normal oilsupply, a coil spring and valve keep the bypass closed, di-recting all of the oil pumped to the engine. When theamount of oil being pumped increases, the pressure be-comes high enough to overcome the force of the spring.

This opens the valve of the oil pressure regulator, allowingthe excess oil to flow through the valve and drain back tothe oil pan.

OIL PANThe engine oil pan is mounted to the bottom of the cylinderblock. The engine oil pan houses the crankcase and ismade of cast aluminum.

Engine oil is pumped from the oil pan by the oil pump. Afterit passes through the oil filter, it is fed through two pathsto lubricate the cylinder block and the cylinder head. In onepath, the oil is pumped through oil passages in the crank-shaft to the connecting rods, and to the pistons and cylin-ders. It then drains back to the oil pan. In the second path,the oil is pumped through passages to the camshaft. Theoil passes through the internal passage ways in the cam-shafts to lubricate the valve assemblies before drainingback to the oil pan.

EXHAUST MANIFOLDA single four–port, rear–takedown manifold is used. Themanifold is designed to direct escaping exhaust gases outof the combustion chambers with a minimum of back pres-sure. The oxygen sensor is mounted to the exhaust man-ifold.

INTAKE MANIFOLDThe intakemanifold has four independent long ports andutilizes an inertial supercharging effect to improve enginetorque at low and moderate speeds.

CAMSHAFTSThis engine is a dual overhead camshaft (DOHC) type,which means there are two camshafts. One camshaft op-erates the intake valves, and the other camshaft operatesthe exhaust valves. The camshafts sit in journals on thetop of the engine (in the cylinder head) and are held inplace by camshaft caps. The camshaft journals of the cyl-inder head are drilled for oil passages. Engine oil travelsto the camshafts under pressure where it lubricates eachcamshaft journal. The oil returns to the oil pan throughdrain holes in the cylinder head. The camshaft lobes aremachined into the solid camshaft to precisely open andclose the intake and the exhaust valves the proper dis-tance at the correct time. The camshaft lobes are oiled bysplash action from pressurized oil escaping from the cam-shaft journals.

1C – 12IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

MAINTENANCE AND REPAIR

ON–VEHICLE SERVICE

VALVE COVER

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the breather tube from the valve cover.3. Disconnect the camshaft position sensor.

4. Disconnect all of the necessary vacuum lines.5. Remove the spark plug cover bolts.6. Remove the spark plug cover.7. Disconnect the ignition wires from the spark plugs.8. Remove the valve cover bolts.9. Remove the valve cover washers.

10. Remove the valve cover.11. Remove the valve cover gasket from the valve cov-

er.

DOHC ENGINE MECHANICAL 1C – 13

DAEWOO V–121 BL4

Installation Procedure

1. Apply a small amount of gasket sealant to the cor-ners of the front camshaft caps and the top of therear valve cover–to–cylinder head seal.

2. Install the new valve cover gasket to the valve cov-er.

3. Install the valve cover.4. Install the valve cover washers.5. Install the valve cover bolts.

TightenTighten the valve cover bolts to 8 Nm (71 lb–in).

6. Connect the camshaft position sensor.

7. Connect the ignition wires to the spark plugs.8. Install the spark plug cover.9. Install the spark plug cover bolts.

TightenTighten the spark plug cover bolts to 3 Nm (27 lb–in).

10. Connect all of the necessary vacuum lines.11. Connect the breather tube to the valve cover.12. Connect the negative battery cable.

1C – 14IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

CYLINDER HEAD AND GASKETTools RequiredKM–470–B Angular Torque GaugeJ–28467–B Engine Assembly Lift Support

Removal Procedure

1. Remove the fuel pump fuse.2. Start the engine. After it stalls, crank the engine for

10 seconds to rid the fuel system of fuel pressure.3. Disconnect the negative battery cable.4. Disconnect the powertrain control module

(PCM)/engine control module (ECM) ground termi-nal.

5. Drain the engine coolant. Refer to Section 1D, En-gine Cooling.

6. Disconnect the intake air temperature sensor con-nector.

7. Disconnect the breather tube from the valve cover.8. Disconnect the air intake tube from the throttle

body.

9. Disconnect the electronic ignition system (EI sys-tem) ignition coil connector.

10. Disconnect the pre–converter oxygen sensor con-nector.

11. Disconnect the idle air control valve connector.12. Disconnect the throttle position sensor connector.13. Disconnect the engine coolant temperature sensor

connector.14. Disconnect the coolant temperature sensor connec-

tor.15. Disconnect the camshaft position sensor.

DOHC ENGINE MECHANICAL 1C – 15

DAEWOO V–121 BL4

16. Remove the air filter housing bolts.17. Remove the air filter housing.18. Remove the right front wheel. Refer to Section 2E,

Tires and Wheels.19. Remove the right front splash shield.20. Install the engine assembly lift support J–28467–B.21. Remove the right engine mount bracket and bolts.

22. Disconnect the upper radiator hose at the thermo-stat housing.

23. Remove the serpentine accessory drive belt. Referto Section 6B, Power Steering Pump.

24. Remove the crankshaft pulley bolts.25. Remove the crankshaft pulley.

26. Remove the front timing belt cover bolts.27. Remove the front timing belt cover.

1C – 16IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

28. Remove the timing belt. Refer to ”Timing Belt” inthis section.

29. Disconnect the breather tube at the valve cover.30. Remove the spark plug cover bolts.31. Remove the spark plug cover.32. Disconnect the ignition wires from the spark plugs.33. Remove the valve cover nuts.34. Remove the valve cover washers.35. Remove the valve cover and the valve cover gas-

ket.

Notice : Take extreme care to prevent any scratches,nicks or damage to the camshafts.36. While holding the intake camshaft firmly in place,

remove the intake camshaft gear bolt.37. Remove the intake camshaft gear.38. While holding the exhaust camshaft firmly in place,

remove the exhaust camshaft gear bolt.39. Remove the exhaust camshaft gear.

40. Remove the timing belt automatic tensioner bolts.41. Remove the timing belt automatic tensioner.

DOHC ENGINE MECHANICAL 1C – 17

DAEWOO V–121 BL4

42. Remove the timing belt idler pulley bolt and nut.43. Remove the timing belt idler pulleys.44. Remove the engine mount bolts.45. Remove the engine mount.

46. Remove the rear timing belt cover bolts.47. Remove the rear timing belt cover.

48. Remove the auxiliary catalytic converter nuts at theexhaust manifold.

49. Disconnect all of the necessary vacuum hoses.

1C – 18IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

50. Disconnect the fuel return line at the fuel pressureregulator.

51. Disconnect the fuel feed line at the fuel rail.52. Remove the generator adjusting bracket retaining

bolt and the bracket.53. Disconnect the coolant hose at the rear cylinder

head and ignition coil exhaust gas recirculation(EGR) bracket.

54. Disconnect the surge tank coolant hose at thethrottle body.

55. Remove the fuel rail assembly. Refer toSection 1F,Engine Controls.

56. Remove the generator–to–intake manifold supportbracket bolts at the cylinder head and the intakemanifold.

57. Remove the generator support bracket.58. Remove the intake manifold–to–generator strap

bracket bolt and loosen the bolt on the generator.59. Move the strap clear of the intake manifold.60. Remove the evaporative emission canister purge

solenoid bracket bolt and move the bracket clear.

61. Disconnect the throttle cable at the throttle bodyand the intake manifold.

62. Loosen all of the cylinder head bolts gradually andin the sequence shown.

63. Remove the cylinder head bolts.64. Remove the cylinder head with the intake manifold

and the exhaust manifold attached.Notice : Prevent any engine oil or coolant from enteringthe cylinders when removing the cylinder head.65. Remove the cylinder head gasket.

DOHC ENGINE MECHANICAL 1C – 19

DAEWOO V–121 BL4

Cleaning Procedure1. Clean the gasket surfaces of the cylinder head and

the engine block.2. Make sure the gasket surfaces of the cylinder head

and the engine block are free of nicks and heavyscratches.

3. Clean the cylinder head bolts.4. Inspect the cylinder head for warpage. Refer to

”Cylinder Head and Valve Train Components” inthis section.

Installation Procedure

1. Install the cylinder head gasket.2. Install the cylinder head with the intake manifold

and the exhaust manifold attached.3. Install the cylinder head bolts.4. Tighten the cylinder head bolts gradually and in the

sequence shown.TightenTighten the cylinder head bolts to 25 Nm (18 lb–ft)and turn the bolts another 3 turns of 90 degrees usingthe angular torque gauge KM–470–B.

5. Connect the throttle cable at the throttle body andthe intake manifold.

6. Install the generator–to–intake manifold supportbracket.

7. Install the intake generator–to–manifold supportbracket bolts.

TightenTighten the generator–to–intake manifold supportbracket bolts to the intake manifold to 35 Nm (26 lb–ft).

8. Install the intake manifold support bracket bolt tothe generator.

TightenTighten the intakemanifold support bracket bolt at thegenerator to 20 Nm (15 lb–ft).

9. Connect the surge tank coolant hose at the throttlebody.

10. Connect the coolant hose to the rear cylinder headand ignition coil EGR bracket.

1C – 20IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

11. Connect the fuel feed line at the fuel rail.12. Connect the fuel return line at the fuel rail.13. Connect all of the necessary vacuum hoses.14. Install the fuel rail assembly. Refer to Section 1F,

Engine Controls (DOHC).

15. Install the auxiliary catalytic converter nuts at theexhaust manifold flange.

TightenTighten the auxiliary catalytic converter–to–exhaustmanifold nuts to 40 Nm (30 lb–ft).

16. Install the rear timing belt cover.17. Install the rear timing belt cover bolts.

TightenTighten the rear timing belt cover bolts to 6 Nm (53lb–in).

18. Install the engine mount and retaining bolts.

TightenTighten the engine mount retaining bolts to 60 N·m(44 lb–ft).

19. Install the timing belt automatic tensioner.20. Install the timing belt automatic tensioner bolt.

TightenTighten the timing belt automatic tensioner bolts to 25Nm (18 lb–ft).

21. Install the timing belt idler pulleys.22. Install the timing belt idler pulley nuts.

TightenTighten the timing belt idler pulley bolt to 25 Nm (18lb–ft).

TightenTighten the timing belt idler pulley nut to 25 Nm (18lb–ft).

DOHC ENGINE MECHANICAL 1C – 21

DAEWOO V–121 BL4

23. Install the camshaft gears with the timing marks atthe front.

24. Insert the guide pin of the intake camshaft into the”IN” bore.

25. Insert the guide pin of the exhaust camshaft intothe ”EX” bore.

26. Install the camshaft gears by counterholding on thehex of the camshaft with an open–ended wrench.

27. Install the camshaft gear with a new bolt to thecamshaft.

TightenTighten the intake camshaft gear bolt to 50 Nm (37lb–ft). Using the angular torque gauge KM–470–B,tighten the bolt another 60 degrees plus 15 degrees.

28. While holding the exhaust camshaft firmly in place,install the exhaust camshaft gear bolt.

TightenTighten the exhaust camshaft gear bolt to 50 Nm (37lb–ft). Using the angular torque gauge KM–470–B,tighten the bolt another 60 degrees plus 15 degrees.

29. Apply a small amount of gasket sealant to the cor-ners of the front camshaft caps and to the top ofthe rear valve cover–to–cylinder head seal.

30. Install the valve cover and the valve cover gasket.31. Install the valve cover washers.32. Install the valve cover bolts.

TightenTighten the valve cover bolts to 8 N·m (71 lb–in).

1C – 22IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

33. Connect the ignition wires to the spark plugs.34. Install the spark plug cover.35. Install the spark plug cover bolts.

TightenTighten the spark plug cover bolts to 8 Nm (71 lb–in).

36. Connect the breather tube to the valve cover.37. Align the timing marks on the camshaft gears to the

notches on the valve cover, using the intake gearmark for the intake gear and the exhaust gear markfor the exhaust gear.

38. Align the mark on the crankshaft gear with thenotch at the bottom of the rear timing belt cover.

39. Install the timing belt.40. Check and adjust the timing belt tension. Refer to

”Timing Belt Check and Adjust” in this section.

DOHC ENGINE MECHANICAL 1C – 23

DAEWOO V–121 BL4

41. Install the front timing belt cover.42. Install the front timing belt cover bolts.

TightenTighten the upper and lower front timing belt coverbolts to 6 Nm (53 lb–in).

43. Install the crankshaft pulley.44. Install the crankshaft pulley bolts.

TightenTighten the crankshaft pulley bolts to 20 Nm (15 lb–ft).

45. Install the right engine mount bracket and retainingbolts.

TightenTighten the right engine mount bracket retaining boltsto 60 Nm (44 lb–ft).

46. Remove the engine assembly lift supportJ–28467–B.

47. Install the serpentine accessory drive belt. Refer toSection 6B, Power Steering Pump.

48. Connect the upper radiator hose to the thermostathousing.

49. Install the right front splash shield.50. Install the right front wheel. Refer to Section 2E,

Tires and Wheels.

51. Install the air filter housing.52. Install the air filter housing bolts.

TightenTighten the air filter housing bolts to 8 Nm (71 lb–in).

53. Connect the air intake tube to the throttle body.54. Connect the breather tube to the valve cover.55. Connect the intake air temperature sensor connec-

tor.56. Connect the camshaft position sensor.

1C – 24IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

57. Connect the coolant temperature sensor connector.58. Connect the engine coolant temperature sensor

connector.59. Connect the idle air control valve connector.60. Connect the throttle position sensor connector.61. Install the evaporative emission canister purge so-

lenoid bracket bolt.

TightenTighten the evaporative emission canister purge sole-noid bracket bolt to 5 Nm (44 lb–in).

62. Connect the EI system ignition coil connector.63. Connect the pre–converter oxygen sensor connec-

tor.64. Connect the PCM/ECM ground terminal.65. Install the fuel pump fuse.66. Connect the negative battery ground cable.67. Refill the engine cooling system. Refer to Section

1D, Engine Cooling.

CAMSHAFTS

Removal Procedure

1. Remove the timing belt. Refer to ”Timing Belt” inthis section.

2. Disconnect the breather tube at the valve cover.3. Disconnect the crankcase ventilation tube at the

valve cover.4. Remove the spark plug cover bolts.5. Remove the spark plug cover.6. Disconnect the ignition wires from the spark plugs.7. Disconnect the camshaft position sensor.8. Remove the valve cover bolts.9. Remove the valve cover washers.10. Remove the valve cover and the valve cover gas-

ket.

DOHC ENGINE MECHANICAL 1C – 25

DAEWOO V–121 BL4

Notice : Take extreme care to prevent any scratches,nicks or damage to the camshafts.11. While holding the intake camshaft firmly in place,

remove the intake camshaft gear bolt.12. Remove the intake camshaft gear.13. While holding the exhaust camshaft firmly in place,

remove the exhaust camshaft gear bolt.14. Remove the exhaust camshaft gear.

15. Loosen the camshaft bearing cap bolts in stages ofone–half to one turn.

16. Remove the camshaft bearing cap bolts from thecylinder head.

17. Remove the camshafts.18. Remove the seal ring from the camshafts.Important : The camshaft must detach evenly from thebearing seats in the front guide bearing.19. Check the camshaft and bearing seats for wear and

replace them if necessary.

Installation Procedure

Notice : Take extreme care to prevent any scratches,nicks or damage to the camshafts.

1. Lubricate the camshaft journals and the camshaftcaps with engine oil.

2. Install the intake camshaft.3. Install the intake camshaft bearing caps in their

original positions.4. Install the intake camshaft bearing cap bolts.5. Install the exhaust camshaft.6. Install the exhaust camshaft bearing caps in their

original positions.7. Install the exhaust camshaft bearing cap bolts.8. Tighten the camshaft cap bolts gradually and in the

sequence shown for each camshaft bearing cap.

TightenTighten the camshaft cap bolts to 8 Nm (71 lb–in).

1C – 26IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

9. Measure the intake camshaft end play and the ex-haust camshaft end play. Refer to ”Engine Specifi-cations” in this section.

10. Install the intake camshaft gear.11. While holding the intake camshaft firmly in place,

install the intake camshaft gear bolt.

TightenTighten the intake camshaft gear bolt to 50 Nm (37lb–ft). Using the angular torque gauge KM–470–B,tighten the bolt another 60 degrees plus 15 degrees.

12. Install the exhaust camshaft gear.13. While holding the exhaust camshaft firmly in place,

install the exhaust camshaft gear bolt.

TightenTighten the exhaust camshaft gear bolt to 50 Nm (37lb–ft). Using the angular torque gauge KM–470–B,tighten the bolt another 60 degrees plus 15 degrees.

14. Install the valve cover and the valve cover gasket.15. Install the valve cover washers.16. Install the valve cover bolts.

TightenTighten the valve cover bolts to 8 Nm (71 lb–in).

17. Connect the camshaft position sensor.

DOHC ENGINE MECHANICAL 1C – 27

DAEWOO V–121 BL4

18. Connect the ignition wires to the spark plugs.19. Install the spark plug cover.20. Install the spark plug cover bolts.

TightenTighten the spark plug cover bolts to 3 Nm (27 lb–in).

21. Connect the breather tube to the valve cover.22. Connect the crankcase ventilation tube to the valve

cover.23. Install the timing belt. Refer to ”Timing Belt” in this

section.

TIMING BELT CHECK AND ADJUST

Adjustment Procedure

1. Disconnect the negative battery cable.2. Disconnect the intake air temperature sensor con-

nector.3. Remove the air intake tube from the throttle body.4. Remove the breather tube from the valve cover.

5. Remove the air filter housing bolts.6. Remove the air filter housing.7. Remove the right front wheel. Refer to Section 2E,

Tires and Wheels.8. Remove the right front splash shield.

1C – 28IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

9. Remove the serpentine accessory drive belt. RefertoSection 6B, Power Steering Pump.

10. Remove the crankshaft pulley bolts.11. Remove the crankshaft pulley.12. Remove the right engine mount bracket. Refer to

”Engine Mount”in this section.

13. Remove the front timing belt cover bolts.14. Remove the front timing belt cover.

15. Rotate the crankshaft at least one full turn clock-wise using the crankshaft gear bolt.

16. Align the mark on the crankshaft gear with thenotch at the bottom of the rear timing belt cover.

DOHC ENGINE MECHANICAL 1C – 29

DAEWOO V–121 BL4

17. Align the camshaft gear timing marks. Use the ex-haust gear mark for the exhaust gear and the in-take gear mark for the intake gear, since the gearsare interchangeable

18. Loosen the automatic tensioner bolt. To relieve thebelt tension, turn the hex–key tab counterclockwise.

19. Rotate the automatic tensioner hex–key tab clock-wise until the adjust arm pointer of the timing beltautomatic tensioner is aligned with the notch in thetiming belt automatic tensioner bracket.

20. Tighten the automatic tensioner bolt.21. Rotate the crankshaft two full turns clockwise using

the crankshaft gear bolt.22. Check the automatic tensioner pointer.

1C – 30IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

23. When the adjust arm pointer of the timing belt auto-matic tensioner is aligned with the notch on the tim-ing belt automatic tensioner bracket, the belt is ten-sioned correctly.

TightenTighten the automatic tensioner bolt to 25 Nm (18 lb–ft).

24. Install the front timing belt cover.25. Install the front timing belt cover bolts.

TightenTighten the front timing belt cover bolts to 6 Nm (53lb–in).

26. Install the crankshaft pulley.27. Install the crankshaft pulley bolts.

TightenTighten the crankshaft pulley bolt to 20 Nm (15 lb–ft).

28. Install the right engine mount bracket. Refer to”En-gine Mount”in this section.

29. Install the serpentine accessory drive belt. Refer toSection 6B, Power Steering Pump.

DOHC ENGINE MECHANICAL 1C – 31

DAEWOO V–121 BL4

30. Install the right front splash shield.31. Install the right front wheel. Refer to Section 2E,

Tires and Wheels.32. Install the air filter housing.33. Install the air filter housing bolts.

TightenTighten the air filter housing bolts to 8 Nm (71 lb–in).

34. Connect the air intake tube to the throttle body.

35. Connect the breather tube to the valve cover.36. Connect the intake air temperature sensor connec-

tor.37. Connect the negative battery cable.

TIMING BELT

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the intake air temperature sensor con-

nector.3. Disconnect the air intake tube from the throttle

body.4. Disconnect the breather tube from the valve cover.

1C – 32IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

5. Remove the air filter housing bolts.6. Remove the air filter housing.7. Remove the right front wheel. Refer to Section 2E,

Tires and Wheels.8. Remove the right front splash shield.

9. Remove the serpentine accessory drive belt. RefertoSection 6B, Power Steering Pump.

10. Remove the crankshaft pulley bolts.11. Remove the crankshaft pulley.12. Remove the right engine mount bracket. Refer to

”Engine Mount” in this section.

13. Remove the front timing belt cover bolts.14. Remove the front timing belt cover.

DOHC ENGINE MECHANICAL 1C – 33

DAEWOO V–121 BL4

15. Using the crankshaft gear bolt, rotate the crank-shaft clockwise until the timing mark on the crank-shaft gear is aligned with the notch at the bottom ofthe rear timing belt cover.

Notice : The camshaft gears must align with the notch onthe valve cover or damage to the engine could result.16. Align the camshaft gears with the notch on the

valve cover.Important : Use the intake gear mark for the intake cam-shaft gear and the exhaust gear mark for the exhaust cam-shaft gear since both gears are interchangeable.

17. Remove the timing belt.18. Loosen the automatic tensioner bolt. Turn the

hexkey tab to relieve belt tension.

1C – 34IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

Installation Procedure

1. Align the timing mark on the crankshaft gear withthe notch on the bottom of the rear timing belt cov-er.

2. Align the timing marks on the camshaft gears, us-ing the intake gear mark for the intake gear and theexhaust gear mark for the exhaust gear.

3. Install the timing belt.

DOHC ENGINE MECHANICAL 1C – 35

DAEWOO V–121 BL4

4. Turn the hex–key tab in a clockwise direction totension the belt. Turn until the pointer aligns withthe notch.

5. Install the automatic tensioner bolt.

TightenTighten the automatic tensioner bolt to 25 Nm (18 lb–ft).

6. Rotate the crankshaft two full turns clockwise usingthe crankshaft pulley bolt.

7. Recheck the automatic tensioner pointer.

8. Install the front timing belt cover.9. Install the front timing belt cover bolts.

TightenTighten the front timing belt cover bolts to 6 Nm (53lbin).

10. Install the right engine mount bracket. Refer to ”En-gine Mounts” in this section.

11. Install the crankshaft pulley.12. Install the crankshaft pulley bolts.

TightenTighten the crankshaft pulley bolts to 20 Nm (15 lb–ft).

1C – 36IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

13. Install the serpentine accessory drive belt. Refer toSection 2E, Tires and Wheels.

14. Install the right front splash shield.15. Install the right front wheel. Refer to Section 6B,

Power Steering Pump.16. Install the air filter housing.17. Install the air filter housing bolts.

TightenTighten the air filter housing bolts to 8 Nm (71 lb–in).

18. Connect the air intake tube to the throttle body.19. Connect the breather tube to the valve cover.20. Connect the intake air temperature sensor connec-

tor.21. Connect the negative battery cable.

OIL PAN

Removal Procedure

1. Disconnect the negative battery cable.2. Drain the engine oil from the engine crankcase.3. Disconnect the post–converter heated oxygen sen-

sor.4. Remove the auxiliary catalytic converter upper

flange nuts from the exhaust manifold and the sup-port bracket bolts.

5. Remove the front muffler pipe retaining nuts fromthe main catalytic converter.

6. Remove both catalytic converters as a unit.

DOHC ENGINE MECHANICAL 1C – 37

DAEWOO V–121 BL4

7. Remove the oil pan flange–to–transaxle retainingbolts.

8. Remove the oil pan retaining bolts.9. Remove the oil pan from the engine block.

Cleaning Procedure1. Clean the oil pan sealing surface.2. Clean the engine block sealing surface.3. Clean the oil pan retaining bolts.4. Clean the oil pan attaching bolt holes in the engine

block.5. Clean the oil pan splash shield.

1C – 38IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

Installation Procedure

1. Coat the new oil pan gasket with sealant.Important : Install the oil pan within 5 minutes after apply-ing the liquid gasket to the oil pan.2. Install the oil pan to the engine block.3. Install the oil pan retaining bolts.

TightenTighten the oil pan retaining bolts to 10 Nm (89 lb–in).

4. Install the oil pan flange–to–transaxle retainingbolts.

TightenTighten the oil pan flange–to–transaxle bolts to 40Nm (30 lb–ft).

5. Install the catalytic converters.

TightenTighten the auxiliary catalytic converter–to–exhaustmanifold nuts to 40 Nm (30 lb–ft).

DOHC ENGINE MECHANICAL 1C – 39

DAEWOO V–121 BL4

TightenTighten the exhaust pipe support bracket bolts to 40Nm (30 lb–ft).

TightenTighten the front muffler pipe–to–main catalytic con-verter nuts to 30 Nm (22 lb–ft).

6. Connect the post–converter oxygen sensor.7. Connect the negative battery cable.8. Refill the engine crankcase with engine oil.

OIL PUMPTools RequiredKM–498–B Pressure GaugeKM–135 Adapter

Engine Oil Pressure Inspection Procedure

1. Remove the right front wheel well splash shield.2. Disconnect the oil pressure switch connector.

3. Install the adapter KM–135 in place of the oil pres-sure switch.

4. Connect the pressure gauge KM–498–B to theadapter.

5. Start the engine and check the oil pressure at idlespeed and engine temperature of 80³C (176³F).The minimum oil pressure should be 30 kPa (4.35psi).

6. Stop the engine and remove the pressure gaugeKM–498–B and the adapter KM–135.

1C – 40IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

7. Install the oil pressure switch.

TightenTighten the oil pressure switch to 40 Nm (30 lb–ft).

8. Connect the oil pressure switch connector.9. Install the right front wheel well splash shield.10. Check the oil level. Add oil until it reaches the full

mark.

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the rear timing belt cover. Refer to ”Rear

Timing Belt Cover” in this section.3. Disconnect the oil pressure switch connector.

4. Remove the oil pan. Refer to ”Oil Pan” in this sec-tion.

5. Remove the oil pump/pickup tube and supportbracket bolts.

6. Remove the oil pump/pickup tube.

DOHC ENGINE MECHANICAL 1C – 41

DAEWOO V–121 BL4

7. Remove the oil pump retaining bolts.8. Carefully separate the oil pump and gasket from

the engine block and oil pan.9. Remove the oil pump.

Inspection Procedure

1. Clean the oil pump and the engine block gasketmating surface areas.

2. Remove the safety relief valve bolt.3. Remove the safety relief valve and the spring.4. Remove the oil pump–to–crankshaft seal.

1C – 42IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

5. Remove the oil pump rear cover bolts.6. Remove the rear cover.7. Clean the oil pump housing and all the oil pump

parts.8. Inspect all the oil pump parts for signs of wear. Re-

fer to ”Engine Specifications” in this section. Re-place the worn oil pump parts.

Notice : Pack the oil pump gear cavity with petroleum jellyto ensure an oil pump prime, or engine damage could re-sult.9. Coat all the oil pump parts with clean engine oil.

Install the oil pump parts.10. Apply Loctite± 242 to the oil pump rear cover bolts

and install the cover and bolts.

TightenTighten the oil pump rear cover bolts to 6 Nm (53 lb–in).

11. Install the safety relief valve, the spring, washerand the bolt.

TightenTighten the safety relief valve bolt to 30 Nm (22 lb–ft).

Installation Procedure

1. Apply Loctite± 242 to the oil pump bolts and roomtemperature vulcanizing (RTV) sealant to the newoil pump gasket.

2. Install the gasket to the oil pump and install the oilpump to the engine block with the bolts.

TightenTighten the oil pump bolts to 10 Nm (89 lb–in).

DOHC ENGINE MECHANICAL 1C – 43

DAEWOO V–121 BL4

3. Install a new oil pump–to–crankshaft seal. Coat thelip of the seal with a thin coat of grease.

4. Coat the threads of the oil pump/pickup tube andsupport bracket bolts with Loctite± 242.

5. Install the oil pump/pickup tube and the bolts.

TightenTighten the oil pump/pick–up tube and support brack-et bolts to 10 Nm (89 lb–in).

6. Install the oil pan. Refer to ”Oil Pan” in this section.7. Connect the oil pressure switch connector.8. Install the rear timing belt cover. Refer to ”Rear

Timing Belt Cover” in this section.9. Connect the negative battery cable.

1C – 68IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

UNIT REPAIR

CYLINDER HEAD AND VALVE TRAINCOMPONENTSTools RequiredMKM–571–B GaugeKM–340–0 Cutter SetKM–340–7 Guide DriftKM–340–13 CuttersKM–340–26 CuttersKM–348 Valve Spring CompressorKM–653 AdapterKM–805 Valve Guide Reamer

Disassembly Procedure

1. Remove the cylinder head with the intake manifoldand the exhaust manifold attached. Refer to ”Cylin-der Head and Gasket” in this section.

2. Remove the coolant temperature sensor.3. Remove the camshaft position sensor.4. Remove the exhaust manifold heat shield bolts.5. Remove the exhaust manifold heat shield.6. Remove the exhaust manifold retaining nuts in the

sequence shown.7. Remove the exhaust manifold.8. Remove the exhaust manifold gasket.9. Remove the exhaust manifold studs.

10. Remove the thermostat housing mounting bolts.11. Remove the thermostat housing assembly.12. Remove the fuel rail assembly. Refer to Section 1F,

Engine Controls (DOHC).13. Remove the coolant bypass housing mounting bolts

and the housing.

DOHC ENGINE MECHANICAL 1C – 69

DAEWOO V–121 BL4

14. Remove the intake manifold retaining nuts and re-taining bolt in the sequence shown.

15. Remove the intake manifold.16. Remove the intake manifold gasket.17. Remove the electronic ignition system (EI System)

ignition coil and EGR mounting bracket bolts.18. Remove the EI system ignition coil and EGRmount-

ing bracket and ignition wires.19. Remove the intake manifold studs.20. Remove the spark plugs.

21. Remove the camshaft bearing cap bolts graduallyand in the sequence shown for each camshaft cap.

22. Remove the intake camshaft bearing caps. Main-tain the correct positions for installation.

23. Remove the intake camshaft.24. Remove the intake valve lash adjusters.25. Remove the exhaust camshaft caps. Maintain the

correct positions for installation.26. Remove the exhaust camshaft.27. Remove the exhaust valve lash adjusters.

1C – 70IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

28. Compress the valve springs with the valve springcompressor KM–348 and the adapter KM–653.

29. Remove the valve retainers.30. Remove the valve spring compressor KM–348 and

the adapter KM–653.31. Remove the valve spring caps.32. Remove the valve springs. Maintain the original

position of the valve springs for installation.

33. Remove the valves. Maintain the original position ofthe valves for installation.

34. Remove the valve stem seals.

Cylinder Head Inspection

1. Clean the sealing surfaces.2. Inspect the cylinder head gasket and mating sur-

faces for leaks, corrosion and blow–by.3. Inspect the cylinder head for cracks.4. Inspect the length and width of the cylinder head

using a feeler gauge and a straight edge.5. Check the sealing surfaces for deformation and

warpage. The cylinder head sealing surfaces mustbe flat within 0.025 mm (0.001 inch) maximum.

DOHC ENGINE MECHANICAL 1C – 71

DAEWOO V–121 BL4

6. Measure the height of the cylinder head from seal-ing surface to sealing surface. The cylinder headheight should be 133.975 to 134.025 mm (5.274 to5.276 inches). If the cylinder head height is lessthan 133.9 mm (5.271 inches), replace the cylinderhead.

7. Inspect all threaded holes for damage.8. Inspect valve seats for excessive wear and burned

spots.

Valve Inspection1. Inspect the valve stem tip for wear.2. Inspect the valve retainer grooves and the oil seal

grooves for chips and wear.3. Inspect the valves for burns or cracks.4. Inspect the valve stem for burrs and scratches.5. Inspect the valve stem. The valve stem must be

straight.6. Inspect the valve face for grooving. If the groove is

so deep that refacing the valve would result in asharp edge, replace the valve.

7. Inspect the valve spring. If the valve spring endsare not parallel, replace the valve spring.

8. Inspect the valve spring seating surface of thevalve rotators for wear or gouges. Replace as re-quired.

Cleaning Procedure1. Clean the cylinder head.2. Clean the valve guides.3. Clean all of the threaded holes.4. Clean the valves of carbon, oil, and varnish.

1C – 72IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

Cylinder Head Overhaul

Valve Grind–in

1. Lubricate the valve seat using a fine–grained paste.2. Lift the valve rhythmically from the seat with a com-

mercially–available valve grinding tool in order todistribute the paste.

3. Check the contact pattern on the valve head and inthe cylinder head.

4. Clean the valves, the valve guides, and the cylinderhead.

Valve Grind1. Ensure that there are no crater line burns on the

valve cone.2. The valve may be reground only two times. Do not

grind the valve stem end.3. Ensure that the angle at the valve face is 45 de-

grees.4. Inspect the assembly height of the intake valves

and the exhaust valves.

DOHC ENGINE MECHANICAL 1C – 73

DAEWOO V–121 BL4

Valve Guide – Ream

1. Measure the diameter of the valve guide usinggauge MKM–571–B and a commercially–availableinside micrometer.

Important : Valve oversizes may already have been fittedin production.

2. An oversize service code is on the valve guide andthe valve stem end. The following table gives thecorrect size, reamer, and production code for eachservice.

Size Reamer Production Code

ServiceCode

Normal – – K

0.075 KM–805 1 K1

0.150 2 K2

3. Ream the valve guide from the upper side of thecylinder head to the next oversize.

4. After reaming, cross out the code and emboss thevalve guide with the new code.

1C – 74IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

Valve Seat – Cut1. Place the cylinder head on wooden blocks.2. Cut the intake and the exhaust valve seats using

the guide drift KM–340–7 as follows:

Valve seat – A 45–degree surface using the cut-ter KM–340–13.

Upper correction angle – A 30–degree surfaceusing the cutter KM–340–13.

Lower correction angle – A 60–degree surfaceusing the cutter KM–340–26.

3. Clean the chippings from the cylinder head.4. Inspect the dimension for the valve seat width.

Intake: 1.2 to 1.4 mm (0.047 to 0.055 inch). Exhaust: 1.4 to 1.8 mm (0.055 to 0.070 inch).

5. Inspect the assembly height of the intake valvesand the exhaust valves. If the dimension is exceed-ed, install new valves. Inspect the assembly heightof the intake valves and the exhaust valves again. Ifthe valve assembly height is still too large despitereplacing the valves, replace the cylinder head.

Assembly Procedure

1. Coat the valve stems with engine oil.2. Insert the valves in the cylinder head in their origi-

nal positions.3. Insert the valve spring seats.4. Push the accompanying assembly sleeve onto the

valve stem.5. Insert the new valve stem seat.6. Carefully drive the valve stem seal onto the stop

with light taps.7. Install the valve springs in their original positions.8. Install the valve spring caps.

DOHC ENGINE MECHANICAL 1C – 75

DAEWOO V–121 BL4

9. Compress the valve springs with the valve springcompressor KM–348 and adapter KM–653.

10. Install the valve retainers.11. Remove the valve spring compressor KM–348 and

adapter KM–653.

12. Lubricate the valve lash adjusters with engine oil.13. Install the valve lash adjusters.

14. Install the intake camshaft.15. Install the intake camshaft bearing caps in their

original positions.16. Install the exhaust camshaft.17. Install the exhaust camshaft bearing caps in their

original positions.18. Install the camshaft bearing cap bolts.19. Tighten the camshaft bearing cap bolts gradually

and in the sequence shown for each camshaft cap.

TightenTighten the camshaft bearing cap bolts to 8 Nm (71lb–in).

1C – 76IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

20. Install the spark plugs.

TightenTighten the spark plugs to 20 Nm (15 lb–ft).

21. Install the EI system ignition coil and EGR mount-ing bracket.

22. Install the EI system ignition coil and EGR mount-ing bracket bolts.

TightenTighten the EI system ignition coil and EGR mountingbracket bolts to 25 Nm (18 lb–ft).

23. Install the intake manifold studs.24. Install the intake manifold gasket.25. Install the intake manifold.26. Install the intake manifold retaining nuts and retain-

ing bolt in the sequence shown.

TightenTighten the intake manifold retaining nuts and retain-ing bolt to 22 Nm (16 lb–ft).

27. Install the fuel rail assembly. Refer to Section 1F,Engine Controls.

28. Install the thermostat housing assembly.29. Install the thermostat housing mounting bolts.

TightenTighten the thermostat housing mounting bolts to 15Nm (11 lb–ft).

30. Install the coolant bypass housing and mountingbolts.

TightenTighten the coolant bypass housing and mountingbolts to 15 Nm (11 lb–ft).

31. Install the camshaft position sensor.

TightenTighten the camshaft position sensor bolts to 12 Nm(106 lb–in).

DOHC ENGINE MECHANICAL 1C – 77

DAEWOO V–121 BL4

32. Install the exhaust manifold studs.33. Install the exhaust manifold gasket.34. Install the exhaust manifold.35. Install the exhaust manifold retaining nuts in the

sequence shown.

TightenTighten the exhaust manifold retaining nuts to 15 Nm(11 lb–ft).

36. Install the exhaust manifold heat shield.37. Install the exhaust manifold heat shield bolts.

TightenTighten the exhaust manifold heat shield bolts to 8Nm (71 lb–in).

38. Install the cylinder head with the intake manifoldand the exhaust manifold attached. Refer to ”Cylin-der Head and Gasket” in this section.

CRANKSHAFTTools RequiredKM–412 Engine Overhaul StandKM–470–B Angular Torque GaugeKM–635 or J–36972 Crankshaft Rear Oil Seal Installer

Notice : Take extreme care to prevent any scratches,nicks, or damage to the camshafts.

Disassembly Procedure

1. Remove the engine. Refer to ”Engine” in this sec-tion.

2. Remove the flywheel or flexible plate bolts.3. Remove the flywheel or the flexible plate.

4. Remove the crankshaft rear oil seal.5. Mount the engine assembly on the engine overhaul

stand KM–412.

1C – 78IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

6. Remove the front timing belt cover bolts.7. Remove the front timing belt cover.8. Remove the crankshaft pulley bolts.9. Remove the crankshaft pulley.

10. Loosen the timing belt automatic tensioner bolt.11. Rotate the timing belt automatic tensioner hex–key

clockwise to release the tension.12. Remove the timing belt idler pulley bolt and nut.13. Remove the timing belt idler pulleys.14. Remove the timing belt.15. Remove the engine mount retaining bolts.16. Remove the engine mount.

17. Disconnect the crankcase breather tubes from thevalve cover.

18. Remove the spark plug cover bolts.19. Remove the spark plug cover.20. Disconnect the ignition wires from the spark plugs.21. Remove the valve cover bolts.22. Remove the valve cover washers.23. Remove the valve cover and the valve cover gas-

ket.

DOHC ENGINE MECHANICAL 1C – 79

DAEWOO V–121 BL4

Notice : Take extreme care to prevent any scratches,nicks or damage to the camshafts.24. While holding the intake camshaft firmly in place,

remove the intake camshaft bolt.25. Remove the intake camshaft gear.26. While holding the exhaust camshaft firmly in place,

remove the exhaust camshaft bolt.27. Remove the exhaust camshaft gear.

28. Remove the crankshaft timing belt gear.

29. Remove the rear timing belt cover bolts and cover.

1C – 80IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

30. Rotate the engine on the engine overhaul standKM–412.

31. Remove the oil pan retaining bolts.32. Remove the oil pan.33. Remove the oil pump/pickup tube bolts.34. Remove the oil pump/pickup tube.35. Remove the lower block support bracket/splash

shield bolts.36. Remove the splash shield.37. Remove the lower block support bracket bolts.38. Remove the lower block support bracket.

39. Remove the oil pump retaining bolts.40. Remove the oil pump.

DOHC ENGINE MECHANICAL 1C – 81

DAEWOO V–121 BL4

41. Mark the order of the connecting rod bearing caps.42. Remove the connecting rod bearing cap bolts for all

of the pistons.43. Remove the connecting rod bearing caps and the

lower connecting rod bearings.

44. Mark the order of the crankshaft bearing caps.45. Remove the crankshaft bearing cap bolts.46. Remove the crankshaft bearing caps and the lower

crankshaft bearings.47. Remove the crankshaft.48. Clean any necessary parts.

Assembly Procedure

1. Coat the crankshaft bearings with engine oil.2. If replacing the crankshaft, transfer the pulse pick–

up sensor disc to the new crankshaft.

1C – 82IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

3. Install the crankshaft.4. Install the lower crankshaft bearings in the bearing

caps.5. Inspect the crankshaft end play with the crankshaft

bearings installed.6. Check for permissible crankshaft end play. Refer

to”Engine Specifications”in this section.

7. With the crankshaft mounted on the front and rearcrankshaft bearings, check the middle crankshaftjournal for permissible out–of–round (runout). Referto ”Engine Specifications”in this section.

Important : Grease the crankshaft journals and lubricatethe crankshaft bearings slightly so that the plastic gaugingthread does not tear when the crankshaft bearing caps areremoved.8. Inspect all of the crankshaft bearing clearances us-

ing a commercially available plastic gauging (ductileplastic threads).

9. Cut the plastic gauging threads to the length of thebearing width. Lay them axially between the crank-shaft journals and the crankshaft bearings.

10. Install the crankshaft bearing caps and the bolts.

TightenTighten the crankshaft bearing cap bolts to 50 Nm(26 lb–ft). Use the angular torque gauge, KM–470–B,to tighten the crankshaft bearings +45 degrees +another 15 degrees.

DOHC ENGINE MECHANICAL 1C – 83

DAEWOO V–121 BL4

11. Remove the crankshaft bearing cap bolts and thecaps.

12. Measure the width of the flattened plastic thread ofthe plastic gauging using a ruler. (Plastic gauging isavailable for different tolerance ranges.)

13. Inspect the bearing clearance for permissible toler-ance ranges. Refer to ”Engine Specifications”in thissection.

14. Apply a bead of adhesive sealing compound to thegrooves of the crankshaft bearing caps.

15. Install the crankshaft bearing caps to the engineblock.

16. Tighten the crankshaft bearing caps using newbolts.

TightenTighten the crankshaft bearing cap bolts to 15 Nm(26 lb–ft). Use the angular torque gauge, KM–470–B,to tighten the crankshaft bearings +45 degrees +another 15 degrees.

Important : Grease the connecting rod journals and lubri-cate the connecting rod bearings slightly so that the plasticgauging thread does not tear when the connecting rodbearing caps are removed.17. Inspect all of the connecting rod bearing clearances

using a commercially available plastic gauging(ductile plastic threads).

18. Cut the plastic gauging threads to the length of theconnecting rod bearing width. Lay them axially be-tween the connecting rod journals and the connect-ing rod bearings.

19. Install the connecting rod bearing caps.

TightenTighten the connecting rod bearing cap bolts to 35Nm (26 lb–ft). Use the angular torque gaugeKM–470–B to tighten the connecting rod bearing capbolts to +45 degrees plus one turn of 15 degrees.

1C – 84IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

20. Remove the connecting rod bearing caps.21. Measure the width of the flattened plastic thread of

the plastic gauging using a ruler. (Plastic gauging isavailable for different tolerance ranges.)

22. Inspect the bearing clearance for permissible toler-ance ranges. Refer to ”Engine Specifications”in thissection.

23. Install the connecting rod bearing caps to the con-necting rods.

24. Tighten the connecting rod bearing caps using newbolts.

TightenTighten the connecting rod bearing cap bolts to 35Nm (26 lb–ft). Use the angular torque gauge,KM–470–B, to tighten the connecting rod cap bolts to+45 degrees plus one turn of 15 degrees.

25. Install the oil pump.26. Install the oil pump retaining bolts.

TightenTighten the oil pump retaining bolts to 10 Nm (89 lb–in).

DOHC ENGINE MECHANICAL 1C – 85

DAEWOO V–121 BL4

27. Install the lower block support bracket and bolts.

TightenTighten the lower block support bolts to 35 Nm (26lb–ft).

28. Install the lower block support bracket splash shieldand bolts.

TightenTighten the lower block support bracket and splashshield bolts to 35 Nm (26 lb–ft).

29. Install the oil pump/pick–up tube.30. Install the oil pump/pick–up tube bolts.

TightenTighten the oil pump/pick–up tube bolts to 10 Nm (89lb–in).

31. Install the oil pan gasket to the oil pan.32. Install the oil pan.Important : Install the oil pan within 5 minutes after apply-ing the liquid gasket to the oil pan.33. Install the oil pan retaining bolts.

TightenTighten the oil pan retaining bolts to 10 Nm (89 lb–in).

34. Rotate the engine on the engine overhaul standKM–412.

1C – 86IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

35. Install the rear timing belt cover.36. Install the rear timing belt cover bolts.

TightenTighten the rear timing belt cover bolts to 7 Nm (62lb–in).

37. Install the crankshaft timing belt drive gear and thebolt.

TightenTighten the crankshaft timing belt drive gear bolt to135 Nm (100 lb–ft) plus 30³ to 10³ using the torqueangular gauge KM–470–B.

38. Install the engine mount and the retaining bolts.

TightenTighten the engine mount retaining bolts to 60 Nm(44 lb–ft).

39. Install the timing belt automatic tensioner.40. Install the timing belt automatic tensioner bolts.

TightenTighten the timing belt automatic tensioner bolts to 25Nm (18 lb–ft).

41. Install the timing belt idler pulley.42. Install the timing belt idler pulley bolt and nut.

TightenTighten the timing belt idler pulley bolt to 25 N·m (18lb–ft).

TightenTighten the timing belt idler pulley nut to 25 Nm (18lb–ft).

Notice : Take extreme care to prevent any scratches,nicks or damage to the camshafts.43. Install the intake camshaft gear.44. Install the intake camshaft gear bolt while holding

the intake camshaft firmly in place.

TightenTighten the intake camshaft gear bolt to 50 Nm (37lb–ft).

45. Install the exhaust camshaft gear.46. Install the exhaust camshaft gear bolt while holding

the exhaust camshaft firmly in place.

TightenTighten the exhaust camshaft gear bolt to 50 Nm (37lb–ft). Using the angular torque gauge KM–470–B,tighten the intake and the exhaust camshaft gearbolts another 60 degrees plus 15 degrees.

DOHC ENGINE MECHANICAL 1C – 87

DAEWOO V–121 BL4

47. Install the timing belt. Refer to ”Timing Belt” in thissection.

48. Adjust the timing belt tension. Refer to ”Timing BeltCheck and Adjust” in this section.

49. Apply a small amount of gasket sealant to the cor-ners of the front camshaft caps and to the top ofthe rear valve cover to cylinder head seal.

50. Install the valve cover and the valve cover gasket.51. Install the valve cover washers.52. Install the valve cover bolts.

TightenTighten the valve cover bolts to 8 Nm (71 lb–in).

53. Connect the ignition wires to the spark plugs.54. Install the spark plug cover.55. Install the spark plug cover bolts.

TightenTighten the spark plug cover bolts to 8 Nm (71 lb–in).

56. Connect the crankcase breather tube to the valvecover.

57. Install the front timing belt cover.58. Install the front timing belt cover bolts.

TightenTighten the front timing belt cover bolts to 6 Nm (53lb–in).

59. Install the engine lifting device.60. Remove the engine from the engine overhaul stand

KM–412.

61. Install a new crankshaft rear oil seal using installerJ–36972 (or KM–635).

1C – 88IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

62. Install the flywheel or flexible plate.63. Install the flywheel or the flexible plate bolts.

TightenTighten the flywheel bolts to 65 Nm (48 lb–ft). Usethe angular torque gauge KM–470–B to tighten theflywheel bolts to 30 degrees plus 15 degrees. For theautomatic transmission, tighten the flexible plate boltsto 65 Nm (48 lb–ft).

64. Install the engine. Refer to ”Engine”in this section.

CRANKSHAFT BEARINGS ANDCONNECTING ROD BEARINGS –GAUGING PLASTICTools Required

KM–470–B Angular Torque Gauge

Inspection Procedure – Crankshaft

1. Coat the crankshaft bearings with engine oil.2. Install the upper crankshaft bearings into the engine

block crankshaft journals.3. Install the lower crankshaft bearings into the crank-

shaft bearing caps.4. Install the crankshaft.5. Inspect the crankshaft end play with the crankshaft

bearings installed.6. Check for permissible crankshaft end play. Refer to

”Engine Specifications”in this section.7. With the crankshaft mounted on the front and rear

crankshaft bearings, check the middle crankshaftjournal for permissible out–of–round (runout). Referto ”Engine Specifications”in this section.

DOHC ENGINE MECHANICAL 1C – 89

DAEWOO V–121 BL4

Important : Grease the crankshaft journals and lubricatethe crankshaft bearings slightly so that the plastic gaugingthread does not tear when the crankshaft bearing caps areremoved.8. Inspect all of the crankshaft bearing clearances us-

ing a commercially available plastic gauging (ductileplastic threads).

9. Cut the plastic gauging threads to the length of thebearing width. Lay them axially between the crank-shaft journals and the crankshaft bearings.

10. Install the crankshaft bearing caps.11. Install the crankshaft bearing cap bolts.

TightenTighten the crankshaft bearing cap bolts to 50 Nm(37 lb–ft). Using the angular torque gaugeKM–470–B, tighten the crankshaft bearing cap boltsto +45 degrees +15 degrees.

12. Remove the crankshaft bearing caps.13. Measure the width of the flattened plastic thread of

the plastic gauging using a ruler. (Plastic gauging isavailable for different tolerance ranges.)

14. Inspect the bearing clearances for permissible toler-ance ranges. Refer to ”Engine Specifications”in thissection.

1C – 90IDOHC ENGINE MECHANICAL

DAEWOO V–121 BL4

Inspection Procedure – Connecting Rods

1. Coat the connecting rod bearings with engine oil.2. Install the upper connecting rod bearings into the

connecting rod journals.3. Install the lower connecting rod bearings into the

connecting rod bearing caps.

Important : Grease the connecting rod journals and lubri-cate the connecting rod bearings slightly so that the plasticgauging thread does not tear when the connecting rodbearing caps are removed.

4. Inspect all of the connecting rod bearing clearancesusing a commercially available plastic gauging(ductile plastic threads).

5. Cut the plastic gauging threads to the length of thebearing width. Lay them axially between the con-necting rod journals and the connecting rod bear-ings.

6. Install the connecting rod bearing caps.7. Install the connecting rod bearing cap bolts.

TightenTighten the connecting rod cap bolts to 35 Nm (26 lb–ft). Using the angular torque gauge KM–470–B, tight-en the connecting rod cap bolts to +45 degrees plusone turn of 15 degrees.

8. Remove the connecting rod bearing caps.9. Measure the width of the flattened plastic thread of

the plastic gauging using a ruler. (Plastic gauging isavailable for different tolerance ranges.)

10. Inspect the bearing clearance for permissible toler-ance ranges. Refer to ”Engine Specifications”in thissection.

SECTION : 1D

ENGINE COOLINGCAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a toolor equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will helpprevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

TABLE OF CONTENTSSPECIFICATIONS 1D–2. . . . . . . . . . . . . . . . . . . . . . . . . .

CAPACITY 1D–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FASTENER TIGHTENING SPECIFICATIONS 1D–2. . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS 1D–2. . . . . . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS TABLE 1D–2. . . . . . . . . . . . . . . . . . .

DIAGNOSIS 1D–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

THERMOSTAT TEST 1D–3. . . . . . . . . . . . . . . . . . . . . .

SURGE TANK CAP TEST 1D–3. . . . . . . . . . . . . . . . . .

COOLING SYSTEM DIAGNOSIS 1D–4. . . . . . . . . . . .

COMPONENT LOCATOR 1D–5. . . . . . . . . . . . . . . . . . . .

RADIATOR/FAN 1D–5. . . . . . . . . . . . . . . . . . . . . . . . . . .

COOLANT PUMP/THERMOSTAT (2.0L DOHC) 1D–6. . . . . . . . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE AND REPAIR 1D–7. . . . . . . . . . . . . . .

On–Vehicle Service 1D–7. . . . . . . . . . . . . . . . . . . . . . . . . .

DRAINING AND REFILLING THE COOLINGSYSTEM 1D–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

THERMOSTAT 1D–8. . . . . . . . . . . . . . . . . . . . . . . . . . . .

COOLANT PUMP 1D–10. . . . . . . . . . . . . . . . . . . . . . . .

ELECTRIC COOLING FAN– MAIN OR AUXILIARY 1D–11. . . . . . . . . . . . . . . . . . . . . . . . .

SURGE TANK 1D–13. . . . . . . . . . . . . . . . . . . . . . . . . . .

RADIATOR 1D–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE COOLANT TEMPERATURE SENSOR 1D–17. . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION 1D–18. . . . . . . . . . . . . . . . .

RADIATOR 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SURGE TANK 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . .

COOLANT PUMP 1D–18. . . . . . . . . . . . . . . . . . . . . . . .

THERMOSTAT 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . .

ELECTRIC COOLING FAN 1D–18. . . . . . . . . . . . . . . .

COOLANT TEMPERATURE SENSOR 1D–19. . . . . .

ENGINE COOLANT TEMPERATURE SENSOR 1D–19. . . . . . . . . . . . . . .

ENGINE BLOCK HEATER 1D–19. . . . . . . . . . . . . . . . .

1D – 2IENGINE COOLING

DAEWOO V–121 BL4

SPECIFICATIONS

CAPACITY

Application Description

Coolant in the Cooling System 7.0L (1.86 gal) for automatic transaxle7.0L (1.86 gal) for manual transaxle

FASTENER TIGHTENING SPECIFICATIONS

Application Nm Lb–Ft Lb–In

Coolant Pump Mounting Bolts 20 15 –

Engine Coolant Temperature Sensor 10 – 89

Fan Assembly Mounting Bolts 4 – 35

Fan Motor Nut 3.2 – 28

Fan Motor Retaining Screws 4 – 35

Radiator Retaining Bolts, Left Upper and Right Upper 4 – 35

Surge Tank Attaching Bolt 4 – 35

Thermostat Housing Mounting Bolts 15 11 –

SPECIAL TOOLS

SPECIAL TOOLS TABLE

KM–471Adapter

ENGINE COOLING 1D – 3

DAEWOO V–121 BL4

DIAGNOSIS

THERMOSTAT TEST1. Remove the thermostat from the vehicle. Refer to

”Thermostat” in this section.2. Make sure the valve spring is tight when the ther-

mostat is fully closed. If the spring is not tight, re-place the thermostat.

3. Suspend the thermostat and a thermometer in apan of 50/50 mixture of ethylene glycol and water.Do not let the thermostat or the thermometer reston the bottom of the pan because the uneven con-centration of heat on the bottom could result in in-accurate temperature measurements.

4. Heat the pan on a burner.5. Use the thermometer to measure the temperature

of the heated solution.6. The thermostat should begin to open at 87³C

(189³F) and it should be fully open at 102³C(216³F). If it does not open at these temperatures,replace the thermostat.

SURGE TANK CAP TEST

Tools RequiredKM–471 Adapter

The surge tank cap maintains proper pressure, protectsthe system from high pressure by opening a pressurevalve, and protects the coolant hoses from collapsing be-cause of a vacuum.1. Wash any sludge from the surge tank cap and the

valve seat of the vacuum pressure valve for thesurge tank cap.

2. Check for any damage or deformity to the vacuumpressure valve for the surge tank cap. If any dam-age or deformity is found, replace the cap.

3. Install a suitable cooling system pressure tester tothe cap using the adapter KM–471.

4. Pull the vacuum pressure valve open. If the surgetank cap does not seal properly, replace the surgetank cap.

5. Pressurize the cap to 90 to 120 kPa (13.1 to 17.4psi).

6. Wait 10 seconds and check the pressure held bythe tank cap tester.

7. If the pressure held by the cooling system pressuretester falls below 80 kPa (11.6 psi), replace thesurge tank cap.

1D – 4IENGINE COOLING

DAEWOO V–121 BL4

COOLING SYSTEM DIAGNOSIS

Engine Overheats

Checks Action

Check for a loss of the coolant. Add the coolant.

Check for a weak coolant solution. Confirm that the coolant solution is a 50/50 mixture of eth-ylene glycol and water.

Check the front of the radiator for any dirt, leaves, or in-sects.

Clean the front of the radiator.

Check for leakage from the hoses, the coolant pump, theheater, the thermostat housing, the radiator, the coreplugs, or the head gasket.

Replace any damaged components.

Check for a faulty thermostat. Replace a damaged thermostat.

Check for retarded ignition timing. Perform an PCM/ECM code diagnosis. Confirm the integ-rity of the timing belt.

Check for an improperly operating electric cooling fan. Replace the electric cooling fan.

Check for radiator hoses that are plugged or rotted. Replace any damaged radiator hoses.

Check for a faulty water pump. Replace the faulty water pump.

Check for a faulty surge tank cap. Replace the faulty surge tank cap.

Check for a cylinder head or an engine block that iscracked or plugged.

Repair the damaged cylinder head or the damaged engineblock.

Loss of Coolant

Checks Action

Check for a leak in the radiator. Replace the damaged radiator.

Check for a leak in the following locations:

Surge tank. Hose.

Replace the following parts, as needed:

Surge tank. Hose

Check for loose or damaged radiator hoses, heater hoses,and connections.

Reseat the hoses.Replace the hoses or the clamps.

Check for leaks in the coolant pump seal. Replace the coolant pump seal.

Check for leaks in the coolant pump gasket. Replace the coolant pump gasket.

Check for an improper cylinder head torque. Tighten the cylinder head bolts to specifications.Replace the cylinder head gasket, if needed.

Check for leaks in the following locations:

Intake manifold. Cylinder head gasket. Cylinder block plug. Heater core. Radiator drain plug.

Repair or replace any components, as needed, to correctthe leak.

Engine Fails to Reach Normal Operating Temperature or Cool Airfrom the Heater

Checks Action

Check to determine if the thermostat is stuck open or is thewrong type of thermostat.

Install a new thermostat of the correct type and heat range.

Check the coolant level to determine if it is below the MINmark on the surge tank.

Add sufficient coolant to raise the fluid to the specifiedmark on the surge tank.

ENGINE COOLING 1D – 5

DAEWOO V–121 BL4

COMPONENT LOCATOR

RADIATOR/FAN

1. Holder Transmission Fluid Pipe (Automatic Trans-mission Only)

2. Upper Radiator Bumper3. Radiator Bracket4. Bolts5. Radiator6. Radiator Bumper

7. Spring Clamp8. Upper Radiator Hose9. Bolts10. Auxiliary Cooling Fan (Air Conditioning Only)11. Drain Cock12. Main Cooling Fan

1D – 6IENGINE COOLING

DAEWOO V–121 BL4

COOLANT PUMP/THERMOSTAT (2.0L DOHC)

1. O–Ring Seal2. Thermostat3. Thermostat Housing4. Bolt

5. Bolt6. Coolant Pump7. Ring Seal

ENGINE COOLING 1D – 7

DAEWOO V–121 BL4

MAINTENANCE AND REPAIR

On–Vehicle Service

DRAINING AND REFILLING THECOOLING SYSTEM

CAUTION : Do not remove the surge tank cap whilethe engine and the radiator are hot. Scalding fluid andsteam may be blown out under pressure.

1. Place a pan below the vehicle to catch the drainingcoolant.

2. Remove the surge tank cap.3. Unplug the drain plug.CAUTION : Dispose of the used coolant to a usedcoolant holding tank to be picked up with the used oilfor disposal. Never pour the used coolant down thedrain. Ethylene glycol antifreeze is an extremely toxicchemical. Disposing of it into the sewer system or theground water can contaminate the local environment.4. Catch the escaping fluid in a drain pan.5. Remove all sludge and dirt from inside the surge

tank. Refer to ”Surge Tank” in this section.6. Plug the drain cock.7. Add the clean water to the surge tank.8. Fill the tank slowly so that the upper reservoir hose

remains above the water line. This allows the airinside the cooling system to escape.

9. Start the engine.10. Run the engine until the thermostat opens. When

both radiator hoses are hot to the touch, the ther-mostat is open.

11. Stop the engine.12. Repeat Steps 1 through 9 until the drained water is

clear and free of coolant and rust.Notice : Never use an antifreeze mixture more concen-trated than 60 percent antifreeze to 40 percent water. Thesolution freezing point increases above this concentration.13. Fill the cooling system through the surge tank with

a mixture of ethylene glycol antifreeze and water.The mixture must be at least 50 percent antifreeze,and not more than 60 percent antifreeze.

14. Fill the surge tank to the specified MAX mark onthe outside of the tank.

1D – 8IENGINE COOLING

DAEWOO V–121 BL4

THERMOSTAT

Removal Procedure

CAUTION : To prevent personal injury, do not removethe surge tank cap while the engine and the radiatorare hot because the heat causes the system to remainunder pressure. Scalding fluid and steam may beblown out under pressure.1. Drain the coolant. Refer to ”Draining and Refilling

the Cooling System” in this section.2. Loosen the hose clamp on the upper radiator hose

at the thermostat housing.3. Disconnect the upper radiator hose from the ther-

mostat housing.

4. Remove the mounting bolts that hold the thermo-stat housing to the cylinder head.

5. Remove the thermostat housing from the cylinderhead.

6. Remove the O–ring seal from the thermostat hous-ing.

7. Remove the thermostat from the thermostat hous-ing by pressing the thermostat mounting flangedownward and then rotating the flange clockwise.

8. Inspect the valve seat for foreign matter that couldprevent the valve from sealing properly.

9. Inspect the thermostat for proper operation. Referto ”Thermostat Test” in this section.

10. Clean the thermostat housing and the cylinder headmating surfaces.

ENGINE COOLING 1D – 9

DAEWOO V–121 BL4

Installation Procedure

1. Install the thermostat into the thermostat housingby pressing the thermostat mounting flange down-ward and then rotating the flange counterclockwise.Rotate the thermostat mounting flange until it isseated in the thermostat housing recesses.

2. Coat the sealing surface of a new O–ring seal withLubriplate±.

3. Install a new O–ring seal into the recess in the ther-mostat housing.

4. Install the thermostat housing to the cylinder head.5. Secure the thermostat housing to the cylinder head

with the mounting bolts.

TightenTighten the thermostat housing mounting bolts (2.0LDOHC) to 15 Nm (11 lb–ft).

6. Connect the upper radiator hose to the thermostathousing.

7. Secure the upper radiator hose to the thermostathousing with a hose clamp.

8. Refill the engine cooling system. Refer to ”Drainingand Refilling the Cooling System” in this section.

1D – 10IENGINE COOLING

DAEWOO V–121 BL4

COOLANT PUMP

Removal Procedure

1. Drain the engine cooling system to a level belowthe thermostat housing. Refer to ”Draining and Re-filling the Cooling System” in this section.

2. Remove the timing belt. Refer toSection 1C, DOHCEngine Mechanical.

3. Remove the timing belt tension roller retaining bolt.4. Remove the timing belt tension roller.

5. Remove the coolant pump mounting bolts.6. Remove the coolant pump from the engine block.7. Remove the ring seal from the coolant pump.

Inspection Cleaning Procedure1. Inspect the coolant pump body for cracks and

leaks.2. Inspect the coolant pump bearing for play or abnor-

mal noise.3. Inspect the coolant pump pulley for excessive wear.

If the coolant pump is defective, replace the coolantpump as a unit.

4. Clean the mating surfaces of the coolant pump andthe engine block.

ENGINE COOLING 1D – 11

DAEWOO V–121 BL4

Installation Procedure

1. Install a new ring seal to the coolant pump.2. Coat the sealing surface of the ring seal with Lubri–

plate±.3. Install the coolant pump to the engine block with

the flange aligned with the recess of the rear timingbelt cover.

4. Secure the coolant pump to the engine block withthe mounting bolts.

TightenTighten the coolant pump mounting bolts (DOHC) to20 Nm (15 lb–ft).

5. Install the timing belt tension roller to the oil pumpwith the flange inserted into the recess of the oilpump.

6. Install the timing belt tension roller bolt. Do nottighten the bolt at this time.

7. Install the timing belt. Refer toSection 1C, DOHCEn–gine Mechanical.

8. Refill the engine cooling system. Refer to ”Drainingand Refilling the Cooling System” in this section.

ELECTRIC COOLING FAN– MAIN ORAUXILIARY

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the cooling fan electrical connector.3. Remove the fan shroud mounting bolts.4. Lift the fan shroud assembly upward, and remove

the fan shroud assembly from the vehicle.

1D – 12IENGINE COOLING

DAEWOO V–121 BL4

5. Remove the fan blade from the fan shroud assem-bly by removing the nut at the center of the fan hub.

6. Turn over the fan shroud assembly.

7. Remove the fan motor retaining screws.8. Remove the fan motor from the shroud.

Installation Procedure

CAUTION : If a fan blade is bent or damaged in anyway, no attempt should be made to repair or reuse thedamaged part. A bent or damaged fan assembly mustbe replaced with a new fan assembly. It is essentialthat fan assemblies remain in proper balance. A fanassembly that is not in proper balance can fail and flyapart during use, creating extreme danger. Properbalance cannot be assured on a fan assembly thathas been bent or damaged.

1. Install the fan motor to the shroud.2. Secure the motor to the shroud with the retaining

screws.

TightenTighten the fan motor retaining screws to 4 Nm (35lb–in).

3. Turn over the fan shroud assembly.

ENGINE COOLING 1D – 13

DAEWOO V–121 BL4

4. Install the fan to the fan shroud assembly with thesingle nut in the center of the fan hub.

TightenTighten the fan motor nut to 3.2 Nm (28 lb–in).

5. Install the fan shroud assembly to the radiator.Important : Be careful to seat the mounting post on thefan shroud into the socket at the radiator left tank. Be sureto slip the tab at the bottom edge of the shroud into the re-taining clip near the center of the radiator.6. Secure the shroud to the top of the radiator with the

mounting bolts.

TightenTighten the fan assembly mounting bolts to 4 Nm (35lb–in).

7. Connect the cooling fan electrical connector.8. Connect the negative battery cable.

SURGE TANK

Removal Procedure

CAUTION : To prevent personal injury, do not removethe surge tank cap while the engine and the radiatorare hot, because the heat causes the system to re-main under pressure. Scalding fluid and steam maybe blown out under pressure.

1. Drain the engine coolant to below the level of thesurge tank.

2. Loosen the return hose clamp and disconnect thereturn hose from the top of the surge tank.

3. Loosen the throttle body hose clamp and discon-nect the throttle body hose from the top of thesurge tank.

4. Loosen the feed hose clamp and disconnect thefeed hose from the bottom of the surge tank.

1D – 14IENGINE COOLING

DAEWOO V–121 BL4

5. Remove the surge tank attaching bolt.6. Remove the surge tank from the support mount.7. Clean the inside and the outside of the surge tank

and the surge tank cap with soap and water.8. Rinse the surge tank and the cap thoroughly.

Installation Procedure

1. Install the surge tank to the support mount.2. Secure the surge tank with the attaching bolt.

TightenTighten the surge tank attaching bolt to 4 Nm (35lbin).

3. Connect the return hose and the throttle body hoseto the top of the surge tank.

4. Connect the feed hose to the bottom of the surgetank.

5. Secure the return hose, the throttle body hose, andthe feed hose to the surge tank with the hoseclamps.

6. Fill the surge tank with the coolant to the centerridge, or to the MAX mark.

ENGINE COOLING 1D – 15

DAEWOO V–121 BL4

RADIATOR

Removal Procedure

1. Disconnect the negative battery cable.2. Drain the engine cooling system. Refer to ”Draining

and Refilling the Cooling System” in this section.3. Remove the main and the auxiliary cooling fans.

Refer to”Electric Cooling Fan – Main or Auxiliary” inthis section.

4. Remove the lower radiator hose clamp.5. Disconnect the lower radiator hose from the radia-

tor.6. Remove the upper radiator hose clamp.7. Disconnect the upper radiator hose from the radia-

tor.

8. Remove the hose clamp from the surge tank hoseat the radiator.

9. Disconnect the surge tank hose from the radiator.10. Disconnect the transaxle fluid cooler pipes from the

lower radiator tank, if equipped.11. Remove the bolt and the transaxle pipe support

clamp from the radiator.12. Remove the left upper radiator retaining bolt.13. Remove the left upper radiator retaining bracket.

14. Remove the right upper radiator retaining bolt.15. Remove the right upper radiator retaining bracket.16. Remove the radiator from the vehicle.Important : The radiator still contains a substantialamount of coolant. Drain the remainder of the coolant fromthe radiator into a drain pan.

1D – 16IENGINE COOLING

DAEWOO V–121 BL4

Installation Procedure

1. Set the radiator into place in the vehicle with theradiator bottom posts in the rubber shock bumpers.

2. Position the radiator retainers in place.3. Install the right upper radiator retainer bracket.4. Install the right upper radiator retaining bolt.

TightenTighten the right upper radiator retaining bolt to 4 Nm(35 lb–in).

5. Install the left upper radiator retainer bracket.6. Install the left upper radiator retaining bolt.

TightenTighten the left upper radiator retaining bolt to 4 Nm(35 lb–in).

ENGINE COOLING 1D – 17

DAEWOO V–121 BL4

7. Connect the transaxle cooler pipes to the lower ra-diator tank, if equipped.

8. Install the transaxle pipe and support clamp to theradiator with a bolt.

9. Connect the surge tank hose to the radiator.10. Secure the surge tank hose with a hose clamp.11. Connect the upper radiator hose and the lower ra-

diator hose to the radiator.12. Secure each hose with a hose clamp.13. Install the main and the auxiliary cooling fans. Refer

to ”Electric Cooling Fan – Main or Auxiliary” in thissection.

14. Refill the engine cooling system. Refer to ”Drainingand Refilling the Cooling System” in this section.

15. Connect the negative battery cable.

ENGINE COOLANT TEMPERATURESENSOR

Removal Procedure1. Disconnect the negative battery cable.2. Drain the coolant to a level below the engine cool-

ant temperature sensor.3. Disconnect the electrical connector from the engine

coolant temperature sensor.4. Remove the temperature sensor from the exhaust

gas recirculation (EGR) valve mounting adapter.

Installation Procedure1. Install the engine coolant temperature sensor into

the threaded hole in the EGR valve mountingadapter.

TightenTighten the engine coolant temperature sensor (2.0LDOHC) to 10 Nm (89 lb–in).

2. Connect the electrical connector to the engine cool-ant temperature sensor.

3. Refill the engine cooling system. Refer to ”Drainingand Refilling the Cooling System” in this section.

4. Connect the negative battery cable.

1D – 18IENGINE COOLING

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

GENERAL DESCRIPTIONThe cooling system maintains the engine temperature atan efficient level during all engine operating conditions.When the engine is cold, the cooling system cools the en-gine slowly, or not at all. The slow cooling of the engine al-lows the engine to warm up quickly.

The cooling system includes a radiator and recovery sub-system, cooling fans, a thermostat and housing, a coolantpump, and a coolant pump drive belt. The timing beltdrives the coolant pump.

All components must function properly in order for thecooling system to operate. The coolant pump draws thecoolant from the radiator. The coolant then circulatesthrough water jackets in the engine block, the intake man-ifold, and the cylinder head. When the coolant reaches theoperating temperature of the thermostat, the thermostatopens. The coolant then goes back to the radiator whereit cools.

The system directs some coolant through the hoses to theheater core. This provides for heating and defrosting. Thesurge tank is connected to the radiator to recover the cool-ant displaced by expansion from the high temperatures.The surge tank maintains the correct coolant level.

The cooling system for this vehicle has no radiator cap orfiller neck. The coolant is added to the cooling systemthrough the surge tank.

RADIATORThis vehicle has a lightweight tube–and–fin aluminum ra-diator. Three models of radiators are available: small,standard, and heavy duty. The three models vary only bysize (capacity). Plastic tanks are mounted on the right andthe left sides of the radiator core.

On vehicles equipped with automatic transaxles, thetransaxle fluid cooler lines run through the left radiatortank.

A radiator drain cock is on the radiator. To drain the coolingsystem, open the drain cock.

SURGE TANKThe surge tank is a transparent plastic reservoir, similar tothe windshield washer reservoir.

The surge tank is connected to the radiator by a hose andto the engine cooling system by another hose. As the ve-hicle is driven, the engine coolant heats and expands. Theportion of the engine coolant displaced by this expansionflows from the radiator and the engine into the surge tank.The air trapped in the radiator and the engine is degassedinto the surge tank.

When the engine stops, the engine coolant cools and con-tracts. The displaced engine coolant is then drawn backinto the radiator and the engine. This keeps the radiatorfilled with the coolant to the desired level at all times andincreases the cooling efficiency.

Maintain the coolant level between the MIN and the MAXmarks on the surge tank when the system is cold.

COOLANT PUMPThe belt–driven centrifugal coolant pump consists of animpeller, a drive shaft, and a belt pulley. The coolant pumpis mounted on the front of the transverse–mounted en-gine, and is driven by the timing belt.

The impeller is supported by a completely sealed bearing.

The coolant pump is serviced as an assembly and, there-fore, cannot be disassembled.

THERMOSTATA wax pellet–type thermostat controls the flow of the en-gine coolant through the engine cooling system. The ther-mostat is mounted in the thermostat housing to the frontof the cylinder head.

The thermostat stops the flow of the engine coolant fromthe engine to the radiator in order to provide faster warm–up, and to regulate the coolant temperature. The thermo-stat remains closed while the engine coolant is cold, pre-venting circulation of the engine coolant through theradiator. At this point, the engine coolant is allowed to cir-culate only throughout the heater core to warm it quicklyand evenly.

As the engine warms, the thermostat opens. This allowsthe engine coolant to flow through the radiator, where theheat is dissipated through the radiator. This opening andclosing of the thermostat permits enough engine coolantto enter the radiator to keep the engine within proper en-gine temperature operating limits.

The wax pellet in the thermostat is hermetically sealed ina metal case. The wax element of the thermostat expandswhen it is heated and contracts when it is cooled.

As the vehicle is driven and the engine warms, the enginecoolant temperature increases. When the engine coolantreaches a specified temperature, the wax pellet elementin the thermostat expands and exerts pressure against themetal case, forcing the valve open. This allows the enginecoolant to flow through the engine cooling system and coolthe engine.

As the wax pellet cools, the contraction allows a spring toclose the valve.

The thermostat begins to open at 87³C (189³F) and is fullyopen at 102³C (216³F). The thermostat closes at 86³C(187³F).

ELECTRIC COOLING FANCAUTION : Keep hands, tools, and clothing awayfrom the engine cooling fans to help prevent personalinjury. This fan is electric and can turn on whether ornot the engine is running.

ENGINE COOLING 1D – 19

DAEWOO V–121 BL4

CAUTION : If a fan blade is bent or damaged in anyway, no attempt should be made to repair or reuse thedamaged part. A bent or damaged fan assemblyshould always be replaced with a new one. Failure todo so can result in personal injury.

The cooling fans are mounted behind the radiator in theengine compartment. The electric cooling fans increasethe flow of air across the radiator fins and across the con-denser on air conditioned (A/C) equipped vehicles. Thishelps to speed cooling when the vehicle is at idle or movingat low speeds.

The main fan size is 300 mm (11.8 inches) in diameter withfive blades to aid the air flow through the radiator and thecondenser. An electric motor attached to the radiator sup-port drives the fan.

A/C models have two fans – the main fan and the auxiliaryfan. The auxiliary fan is 300 mm (11.8 inches) in diameter.

A/C Off or Non–A/C Model

The cooling fans are actuated by the powertraincontrol module (PCM)/engine control module(ECM) using a low–speed cooling fan relay and ahigh–speed cooling fan relay. On A/C–equippedvehicles, a series/parallel cooling fan relay is alsoused.

The PCM/ECM will turn the cooling fans on at lowspeed when the coolant temperature reaches 93³C(199³F) and at high speed when the coolant tem-perature reaches 97³C (207³F).

The PCM/ECM will change the cooling fans fromhigh speed to low speed at 94³C (201³F) and willturn the cooling fans off at 90³C (194³F).

A/C ON The PCM/ECM will turn the cooling fans on at low

speed when the A/C system is on. The PCM/ECMwill change to high speed when the coolant temper-ature reaches 115³C (239³F) or the high side A/Cpressure reaches 1 882 kPa (273 psi).

The cooling fans will return to low speed when thecoolant temperature reaches 112³C (234³F) andthe high side A/C pressure reaches 1 448 kPa (210psi).

COOLANT TEMPERATURE SENSORThe coolant temperature sensor (CTS) uses a thermistorto control the signal voltage to the powertrain control mod-ule (PCM)/engine control module (ECM).

ENGINE COOLANT TEMPERATURESENSORThe engine coolant temperature sensor controls the nstru-ment panel temperature indicator. The engine coolanttemperature sensor is located on the intakemanifold nearthe throttle body on an SOHC engine, and on the cylinderhead under the intake manifold on a DOHC engine.

ENGINE BLOCK HEATERThe vehicle is designed to accept an engine block heaterthat helps to warm the engine and to improve starting incold weather. It also can help to reduce fuel consumptionwhile a cold engine warms up.

The engine block heater is located under the intake man-ifold and uses an existing expansion plug for installation.

Contact your Daewoo Dealer for further information orinstallation.

SECTION : 1F

ENGINE CONTROLSCAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a toolor equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will helpprevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

TABLE OF CONTENTSSPECIFICATIONS 1F–4. . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE DATA DISPLAY TABLES 1F–4. . . . . . . . . . .

ENGINE DATA DISPLAY TABLE DEFINITIONS1F–10

FASTENER TIGHTENING SPECIFICATIONS 1F–13

FUEL SYSTEM SPECIFICATIONS 1F–14. . . . . . . . .

TEMPERATURE VS RESISTANCE 1F–14. . . . . . . . .

SCHEMATIC AND ROUTING DIAGRAMS 1F–15. . . .

PCM/ECM WIRING DIAGRAM (1 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–15. . . . . . . . . . . . . . . . .

PCM/ECM WIRING DIAGRAM (2 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–16. . . . . . . . . . . . . . . . .

PCM/ECM WIRING DIAGRAM (3 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–17. . . . . . . . . . . . . . . . .

PCM/ECM WIRING DIAGRAM (4 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–18. . . . . . . . . . . . . . . . .

PCM/ECM WIRING DIAGRAM (5 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–29. . . . . . . . . . . . . . . . .

PCM/ECM WIRING DIAGRAM (6 OF 6)(IPCM–6KD–/ISFI–6TD) 1F–30. . . . . . . . . . . . . . . . .

CONNECTOR END VIEW (DOHC) 1F–21. . . . . . . . .

COMPONENT LOCATOR 1F–26. . . . . . . . . . . . . . . . . . .

DIAGNOSIS 1F–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SYSTEM DIAGNOSIS 1F–28. . . . . . . . . . . . . . . . . . . . . .

IDLE LEARN PROCEDURE 1F–28. . . . . . . . . . . . . . .

ON–BOARD DIAGNOSTIC (OBD II) SYSTEMCHECK 1F–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PCM/ECM OUTPUT DIAGNOSIS 1F–31. . . . . . . . . .

MULTIPLE PCM/ECM INFORMATION SENSORDTCS SET 1F–33. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE CRANKS BUT WILL NOT RUN 1F–38. . . .

NO MALFUNCTION INDICATOR LAMP 1F–45. . . . .

MALFUNCTION INDICATOR LAMP ON STEADY 1F–48

FUEL SYSTEM DIAGNOSIS 1F–50. . . . . . . . . . . . . . .

FUEL PUMP RELAY CIRCUIT CHECK 1F–53. . . . . .

IGNITION 1 RELAY CIRCUIT CHECK 1F–56. . . . . . .

MANIFOLD ABSOLUTE PRESSURE CHECK 1F–58

PARK/NEUTRAL POSITION SWITCH 1F–60. . . . . . .

IDLE AIR CONTROL SYSTEM CHECK 1F–61. . . . .

IGNITION SYSTEM CHECK 1F–64. . . . . . . . . . . . . . .

ENGINE COOLING FAN CIRCUIT CHECK – WITHA/C 1F–68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DATA LINK CONNECTOR DIAGNOSIS 1F–75. . . . .

FUEL INJECTOR BALANCE TEST 1F–78. . . . . . . . .

EVAP CONTROL SYSTEM DIAGNOSIS 1F–79. . . .

TROUBLE CODE DIAGNOSIS 1F–82. . . . . . . . . . . . . . .

CLEARING TROUBLE CODES 1F–82. . . . . . . . . . . .

DIAGNOSTIC TROUBLE CODES 1F–82. . . . . . . . . .

DTC P0106 MANIFOLD ABSOLUTE PRESSURERATIONALITY 1F–85. . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0107 MANIFOLD ABSOLUTE PRESSURELOW VOLTAGE 1F–87. . . . . . . . . . . . . . . . . . . . . . . .

DTC P0108 MANIFOLD ABSOLUTE PRESSUREHIGH VOLTAGE 1F–90. . . . . . . . . . . . . . . . . . . . . . . .

DTC P0112 INTAKE AIR TEMPERATURE LOWVOLTAGE 1F–93. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0113 INTAKE AIR TEMPERATURE HIGHVOLTAGE 1F–95. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0117 ENGINE COOLANT TEMPERATURELOW VOLTAGE 1F–98. . . . . . . . . . . . . . . . . . . . . . . .

DTC P0118 ENGINE COOLANT TEMPERATUREHIGH VOLTAGE 1F–100. . . . . . . . . . . . . . . . . . . . . . .

DTC P0121 THROTTLE POSITION SENSORRATIONALITY 1F–103. . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0122 THROTTLE POSITION SENSOR LOWVOLTAGE 1F–106. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0123 THROTTLE POSITION SENSOR HIGHVOLTAGE 1F–109. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0125 ENGINE COOLANT TEMPERATUREINSUFFICIENT FOR CLOSED LOOP FUELCONTROL 1F–112. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0131 O2 BANK 1 SENSOR 1 LOW VOLTAGE1F–115

DTC P0132 O2 BANK 1 SENSOR 1 HIGH VOLTAGE1F–118

1F – 2IENGINE CONTROLS

DAEWOO V–121 BL4

DTC P0133 O2 BANK 1 SENSOR 1 SLOWRESPONSE 1F–121. . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0134 O2 BANK 1 SENSOR 1 NO ACTIVITY 1F–125

DTC P0137 O2 BANK 1 SENSOR 2 LOW VOLTAGE1F–128

DTC P0138 O2 BANK 1 SENSOR 2 HIGH VOLTAGE1F–131

DTC P0140 O2 BANK 1 SENSOR 2 NO ACTIVITY 1F–134

DTC P0141 O2 BANK 1 SENSOR 2 HEATER 1F–137

DTC P0171 BANK 1 SYSTEM TOO LEAN 1F–140. .

DTC P0172 BANK 1 SYSTEM TOO RICH 1F–144. .

DTC P0201 INJECTOR 1 CIRCUIT FAULT 1F–148.

DTC P0202 INJECTOR 2 CIRCUIT FAULT 1F–151.

DTC P0203 INJECTOR 3 CIRCUIT FAULT 1F–154.

DTC P0204 INJECTOR 4 CIRCUIT FAULT 1F–157.

DTC P0300 MULTIPLE CYLINDER MISFIREDETECTED 1F–160. . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0301 CYLINDER 1 MISFIRE 1F–165. . . . . . . .

DTC P0302 CYLINDER 2 MISFIRE 1F–169. . . . . . . .

DTC P0303 CYLINDER 3 MISFIRE 1F–173. . . . . . . .

DTC P0304 CYLINDER 4 MISFIRE 1F–177. . . . . . . .

DTC P0325 KNOCK SENSOR SNEF INTERNALMALFUNCTION 1F–181. . . . . . . . . . . . . . . . . . . . . . .

DTC P0327 KNOCK SENSOR CIRCUIT FAULT 1F–183

DTC P0336 58X CRANK POSITIONEXTRA/MISSING PULSES 1F–186. . . . . . . . . . . . .

DTC P0337 58X CRANK POSITION NO SIGNAL 1F–189

DTC P0341 CAM RATIONALITY 1F–192. . . . . . . . . .

DTC P0342 CAM POSITION NO SIGNAL 1F–195. .

DTC P0351 IGNITION CONTROL A CIRCUIT FAULT1F–198

DTC P0352 IGNITION CONTROL B CIRCUIT FAULT1F–200

DTC P0401 EXHAUST GAS RECIRCULATIONINSUFFICIENT FLOW 1F–202. . . . . . . . . . . . . . . . .

DTC P0402 EXHAUST GAS RECIRCULATIONEXCESSIVE FLOW 1F–204. . . . . . . . . . . . . . . . . . . .

DTC P0404 EXHAUST GAS RECIRCULATIONOPEN VALVE POSITION ERROR 1F–208. . . . . . .

DTC P0405 EXHAUST GAS RECIRCULATIONPINTLE POSITION LOW VOLTAGE 1F–212. . . . . .

DTC P0406 EXHAUST GAS RECIRCULATIONPINTLE POSITION HIGH VOLTAGE 1F–216. . . . .

DTC P0420 CATALYST BANK 1 LOW EFFICIENCY 1F–220

DTC P0440 EVAPORATIVE EMISSION SYSTEMLARGE LEAK/LOW TANK VACUUM 1F–222. . . . .

DTC P0442 EVAPORATIVE EMISSION SYSTEMSMALL LEAK 1F–227. . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0443 EVAPORATIVE EMISSION SYSTEMPURGE CONTROL CIRCUIT 1F–231. . . . . . . . . . . .

DTC P0446 EVAPORATIVE EMISSION SYSTEMVENT CONTROL MALFUNCTION 1F–234. . . . . . .

DTC P0449 EVAPORATIVE EMISSION SYSTEMVENT SOLENOID CIRCUIT FAULT 1F–237. . . . . .

DTC P0452 FUEL TANK PRESSURE SENSOR LOWVOLTAGE 1F–240. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0453 FUEL TANK PRESSURE SENSORHIGH VOLTAGE 1F–243. . . . . . . . . . . . . . . . . . . . . . .

DTC P0461 FUEL LEVEL RATIONALITY 1F–246. . .

DTC P0462 FUEL LEVEL LOW VOLTAGE 1F–249. .

DTC P0463 FUEL LEVEL HIGH VOLTAGE 1F–252.

DTC P0480 COOLING FAN RELAY A FANCONTROL CIRCUIT FAULT (WITH A/C) 1F–252. .

DTC P0481 COOLING FAN RELAY B FANCONTROL CIRCUIT FAULT (WITH A/C) 1F–258. .

DTC P0502 VEHICLE SPEED (ENGINE SIDE) NOSIGNAL 1F–261. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0506 IDLE SPEED RPM LOWER THANDESIRED IDLE SPEED 1F–264. . . . . . . . . . . . . . . .

DTC P0507 IDLE SPEED RPM HIGHER THANDESIRED IDLE SPEED 1F–267. . . . . . . . . . . . . . . .

DTC P0532 A/C PRESSURE SENSOR LOW 1F–270

DTC P0533 A/C PRESSURE SENSOR HIGH 1F–273

DTC P0562 SYSTEM VOLTAGE (ENGINE SIDE)TOO LOW 1F–276. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0563 SYSTEM VOLTAGE (ENGINE SIDE)TOO HIGH 1F–279. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P0601 PCM/ECM (ENGINE SIDE) CHECKSUMFAULT 1F–282. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1106 MANIFOLD ABSOLUTE PRESSUREINTERMITTENT HIGH VOLTAGE 1F–283. . . . . . . .

DTC P1107 MANIFOLD ABSOLUTE PRESSUREINTERMITTENT LOW VOLTAGE 1F–285. . . . . . . .

DTC P1109 VARIABLE GEOMETRY INDUCTIONSOLENOID ELECTRICAL FAULT 1F–287. . . . . . . .

DTC P1111 INTAKE AIR TEMPERATUREINTERMITTENT HIGH VOLTAGE 1F–290. . . . . . . .

DTC P1112 INTAKE AIR TEMPERATUREINTERMITTENT LOW VOLTAGE 1F–293. . . . . . . .

DTC P1114 ENGINE COOLANT TEMPERATUREINTERMITTENT LOW VOLTAGE 1F–295. . . . . . . .

DTC P1115 ENGINE COOLANT TEMPERATUREINTERMITTENT HIGH VOLTAGE 1F–297. . . . . . . .

DTC P1121 THROTTLE POSITION SENSORINTERMITTENT HIGH VOLTAGE 1F–300. . . . . . . .

DTC P1122 THROTTLE POSITION SENSORINTERMITTENT LOW VOLTAGE 1F–302. . . . . . . .

DTC P1133 O2 BANK 1 SENSOR 1 TOO FEWTRANSITIONS 1F–304. . . . . . . . . . . . . . . . . . . . . . . .

ENGINE CONTROLS 1F – 3

DAEWOO V–121 BL4

DTC P1134 O2 BANK 1 SENSOR 1 TRANSITIONRATIO 1F–308. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1171 FUEL SUPPLY SYSTEM LEAN DURINGPOWER ENRICH 1F–311. . . . . . . . . . . . . . . . . . . . . .

DTC P1336 58X CRANK POSITION TOOTH ERRORNOT LEARNED 1F–313. . . . . . . . . . . . . . . . . . . . . . .

DTC P1380 ABS ROUGH ROAD ROUGH ROADDATA INVALID 1F–315. . . . . . . . . . . . . . . . . . . . . . . .

DTC P1381 ABS ROUGH ROAD SERIAL DATAFAULT 1F–317. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1391 G SENSOR ROUGH ROADRATIONALITY 1F–319. . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1392 G SENSOR ROUGH ROAD LOWVOLTAGE 1F–322. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1393 G SENSOR ROUGH ROAD HIGHVOLTAGE 1F–325. . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1404 EXHAUST GAS RECIRCULATIONCLOSED VALVE PINTLE ERROR 1F–328. . . . . . .

DTC P1441 EVAPORATIVE EMISSIONCONTINUOUS PURGE FLOW 1F–331. . . . . . . . . .

DTC P1508 IDLE AIR CONTROL COUNTS TOOLOW 1F–334. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1509 IDLE AIR CONTROL COUNTS TOOHIGH 1F–337. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1546 A/C CLUTCH OUTPUT CIRCUIT FAULT1F–340

DTC P1618 PCM/ECM INTERNAL SPICOMMUNICATION 1F–343. . . . . . . . . . . . . . . . . . . .

DTC P1625 PCM/ECM INTERNAL SYSTEM RESET1F–344

DTC P1626 PCM/ECM COMMON ANTI–THEFTERROR NO PASSWORD 1F–345. . . . . . . . . . . . . . .

DTC P1627 PCM/ECM A/D CONVERSION ERROR 1F–348

DTC P1631 PCM/ECM COMMON ANTI–THEFTERROR INCORRECT PASSWORD 1F–349. . . . . .

DTC P1635 PCM/ECM 5 VOLT REFERENCE LINELOW 1F–351. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DTC P1640 ODM INTERNAL SPI COMMUNICATION1F–354

SYMPTOM DIAGNOSIS 1F–357. . . . . . . . . . . . . . . . . . .

IMPORTANT PRELIMINARY CHECKS 1F–357. . . . .

INTERMITTENTS 1F–357. . . . . . . . . . . . . . . . . . . . . . .

HARD START 1F–359. . . . . . . . . . . . . . . . . . . . . . . . . . .

SURGES OR CHUGGLES 1F–361. . . . . . . . . . . . . . . .

LACK OF POWER, SLUGGISHNESS, ORSPONGINESS 1F–364. . . . . . . . . . . . . . . . . . . . . . . .

DETONATION/SPARK KNOCK 1F–365. . . . . . . . . . . .

HESITATION, SAG, STUMBLE 1F–367. . . . . . . . . . . .

CUTS OUT, MISSES 1F–368. . . . . . . . . . . . . . . . . . . . .

POOR FUEL ECONOMY 1F–370. . . . . . . . . . . . . . . . .

ROUGH, UNSTABLE, OR INCORRECT IDLE,STALLING 1F–371. . . . . . . . . . . . . . . . . . . . . . . . . . . .

EXCESSIVE EXHAUST EMISSIONS OR ODORS 1F–374

DIESELING, RUN–ON 1F–375. . . . . . . . . . . . . . . . . . .

BACKFIRE 1F–376. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE AND REPAIR 1F–377. . . . . . . . . . . . .

ON–VEHICLE SERVICE 1F–377. . . . . . . . . . . . . . . . . . .

FUEL TANK 1F–377. . . . . . . . . . . . . . . . . . . . . . . . . . . .

FUEL PUMP 1F–379. . . . . . . . . . . . . . . . . . . . . . . . . . . .

FUEL TANK PRESSURE SENSOR 1F–380. . . . . . . .

FUEL FILTER 1F–381. . . . . . . . . . . . . . . . . . . . . . . . . . .

FUEL RAIL AND INJECTORS 1F–382. . . . . . . . . . . . .

FUEL PRESSURE REGULATOR 1F–384. . . . . . . . . .

ENGINE COOLANT TEMPERATURE SENSOR 1F–385

THROTTLE POSITION SENSOR 1F–386. . . . . . . . . .

THROTTLE BODY 1F–386. . . . . . . . . . . . . . . . . . . . . . .

OXYGEN SENSOR 1F–389. . . . . . . . . . . . . . . . . . . . . .

HEATED OXYGEN SENSOR 1F–389. . . . . . . . . . . . .

INTAKE AIR TEMPERATURE SENSOR 1F–391. . . .

IDLE AIR CONTROL VALVE 1F–391. . . . . . . . . . . . . .

MANIFOLD ABSOLUTE PRESSURE SENSOR1F–392

EXHAUST GAS RECIRCULATION VALVE 1F–394. .

G SENSOR 1F–394. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

EVAPORATIVE EMISSION CANISTER 1F–395. . . .

EVAPORATIVE EMISSION CANISTER PURGESOLENOID 1F–396. . . . . . . . . . . . . . . . . . . . . . . . . . .

CRANKSHAFT POSITION SENSOR 1F–396. . . . . . .

CAMSHAFT POSITION SENSOR 1F–398. . . . . . . . .

POWERTRAIN CONTROL MODULE/ENGINECONTROL MODULE 1F–399. . . . . . . . . . . . . . . . . . .

ELECTRONIC IGNITION SYSTEM IGNITION COIL 1F–400

FUEL CUTOFF SWITCH 1F–401. . . . . . . . . . . . . . . . .

KNOCK SENSOR 1F–402. . . . . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 1F–404. . . . . . . . . . . . . . . . . . . . . . . . . . . .

IGNITION SYSTEM OPERATION 1F–404. . . . . . . . .

ELECTRONIC IGNITION SYSTEM IGNITION COIL 1F–404

CRANKSHAFT POSITION SENSOR 1F–404. . . . . . .

CAMSHAFT POSITION SENSOR 1F–404. . . . . . . . .

IDLE AIR SYSTEM OPERATION 1F–404. . . . . . . . . .

FUEL CONTROL SYSTEM OPERATION 1F–404. . .

EVAPORATIVE EMISSION CONTROL SYSTEMOPERATION 1F–405. . . . . . . . . . . . . . . . . . . . . . . . . .

EVAPORATIVE EMISSION CANISTER 1F–406. . . .

1F – 4IENGINE CONTROLS

DAEWOO V–121 BL4

POSITIVE CRANKCASE VENTILATION SYSTEMOPERATION 1F–406. . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE COOLANT TEMPERATURE SENSOR 1F–406

THROTTLE POSITION SENSOR 1F–406. . . . . . . . . .

CATALYST MONITOR OXYGEN SENSOR 1F–406.

EXHAUST GAS RECIRCULATION VALVE 1F–407. .

INTAKE AIR TEMPERATURE SENSOR 1F–407. . . .

IDLE AIR CONTROL VALVE 1F–407. . . . . . . . . . . . . .

MANIFOLD ABSOLUTE PRESSURE SENSOR1F–408

POWERTRAIN CONTROL MODULE/ENGINECONTROL MODULE 1F–408. . . . . . . . . . . . . . . . . . .

FUEL INJECTOR 1F–408. . . . . . . . . . . . . . . . . . . . . . . .

KNOCK SENSOR 1F–408. . . . . . . . . . . . . . . . . . . . . . .

G SENSOR 1F–409. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FUEL CUTOFF SWITCH 1F–409. . . . . . . . . . . . . . . . .

STRATEGY–BASED DIAGNOSTICS 1F–409. . . . . .

OBD II SERVICEABILITY ISSUES 1F–409. . . . . . . . .

SERIAL DATA COMMUNICATIONS 1F–410. . . . . . . .

ON–BOARD DIAGNOSTIC (OBD II) 1F–411. . . . . . .

COMPREHENSIVE COMPONENT MONITORDIAGNOSTIC OPERATION 1F–411. . . . . . . . . . . . .

COMMON OBD II TERMS 1F–412. . . . . . . . . . . . . . . .

DTC TYPES 1F–413. . . . . . . . . . . . . . . . . . . . . . . . . . . .

READING DIAGNOSTIC TROUBLE CODES 1F–413

PRIMARY SYSTEM–BASED DIAGNOSTICS 1F–415

SPECIFICATIONS

ENGINE DATA DISPLAY TABLESEngine Data Display

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data Value

Engine Speed RPM µ100 rpm from the Desired rpm

Desired Idle Speed RPM PCM/ECM Idle Command (Varieswith the calibration)

Engine Coolant Temperature C – F 85³–115³C(185³–239³F) (Varieswith the coolant temperature)

Intake Air Temperature C – F 10³–80³C(50³–176³F) (Varies withthe coolant temperature)

Throttle Position Angle % 0% (up to 100% at wide openthrottle)

Throttle Position Sensor Volts 0.200–0.900 v (up to 5.0 at wideopen throttle)

MAP kPa 25–35 kPa

BARO kPa 65–100 kPa (varies with altitude andwith the BARO pressure)

EGR Actual Position % 0

EGR Desired Position % 0%

EGR Feedback Volt –

IAC Position Counts 5–60

Cam Speed Activity Counts 0–255

Ignition Voltage Volts 12.0–15.0

Engine Run Time Seconds Varies (since start up)

BPW Bank 1 mS 0–999.9

Air Fuel Ratio Ratio 14.6:1 (Varies)

Spark Degrees Varies

Knock Retard Degrees Varies

ENGINE CONTROLS 1F – 5

DAEWOO V–121 BL4

Scan Tool Parameter Typical Data ValueUnits Displayed

Knock Active Counter Counts 0–255

Knock Present Yes/No No

Calculated Load % 0–100

Vehicle Speed mph 0

Air Condition Pressure Volt 0–5

Oxygen Bank 1 Sensor 1 mV 0–1000 and varying

Oxygen Bank 1 Sensor 2 mV 0–1000 and varying

Decel Fuel Mode Yes/No –

Power Enrichment Mode Yes/No –

Closed Loop Yes/No Yes

Loop Status Close/Open Close

Hot Loop Open Yes/No –

Rich/Lean Bank 1 Rich/Lean –

Short Term Fuel Trim % –100 to 100 (Varies)

Long Term Fuel Trim % –100 to 100 (Varies)

EVAP Purge Solenoid % 0–100

EVAP Vent Solenoid On/Off –

IAC Base Position Counts –

Fuel Trim Cell Cell Number 18–12 at idle (Varies with the airflow, RPM, P/N, and A/C)

Calculated Air Flow g/sec Varies

Weak Cylinder –

Rough Road Sensor Volt

5 Volt Reference Volt

Throttle at Idle Yes/No –

Power Steering Cramp Yes/No –

Air Conditioning Request On/Off OFF

Air Conditioning Clutch On/Off OFF (On with the A/C request)

Fuel Pump On/Off ON

Malfunction Indicator Lamp On/Off –

Upshift Lamp On/Off –

Low Fuel Lamp On/Off –

Hot Open Loop Lamp On/Off –

Variable Gate Intake Long/Short Long

Fuel Trim Learned On/Off –

Fan 1 On/Off OFF (Varies with fan request)

Fan 2 On/Off OFF (Varies with fan request)

Park/Neutral Yes/No Yes

1F – 6IENGINE CONTROLS

DAEWOO V–121 BL4

EVAP Data Display

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data

Engine Speed RPM µ100 rpm from the Desired rpm

Ignition Voltage Volts 12.0–15.0

Engine Coolant Temperature C – F 85³–115³C (185³–239³F) (Varieswith the coolant temperature)

Start Up Coolant Temperature C – F 4³–34³C (39³–93³F) Varies withunderhood temperature when start-

ing

Intake Air Temperature C – F 10³–80³C Varies with underhoodtemperature

Start Up Intake Air Temperature C – F 12³ – 42³C (54³ – 108³F) Varieswith underhood temperature when

starting

Engine Run Time Seconds Varies (Since start up)

Fuel Level Sensor Volt 0.4–4.5

Fuel Gauge On/Off On

EVAP Purge Solenoid % 0–100

EVAP Vent Solenoid On/Off Off

EVAP Tank Vacuum Inches of H2O Depends on Pressure / Vacuum

Throttle Position Angle % 0% (up to 100% at wide openthrottle)

Throttle Position Sensor Volts 0.200–0.900 v (up to 5.0 at wideopen throttle)

IAC Position Counts 5–60

BPW Bank 1 mS 0–999.9

Air Fuel Ratio Ratio 14.6:1 (Varies)

Spark Degrees Varies

MAP kPa 25–35 kPa

BARO kPa 65–100 kPa (varies with altitude andwith the BARO pressure)

Calculated Load % 0–100

Vehicle Speed mph 0

Oxygen Sensor Bank 1 Sensor 1 mV 0––1000 and varying

Oxygen Sensor Bank 1 Sensor 2 mV 0–1000 and varying

ENGINE CONTROLS 1F – 7

DAEWOO V–121 BL4

EGR Data Display

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data

Engine Speed RPM µ100 rpm from the Desired rpm

Ignition Voltage Volts 12.0–15.0

IAC Position Counts 5–60

Engine Coolant Temperature C – F 85³–115³C(185³–239³F) Varies withthe coolant temperature

Throttle Position Angle % 0% (up to 100% at wide openthrottle)

Throttle Position Sensor Volts 0.200–0.900v (up to 5.0 at wideopen throttle)

EGR Actual Position % 0%

EGR Desired Position % 0%

EGR Feedback Volt

EGR Closed Pintle Position Counts –

EGR Trip Sample Count Counts 0

EGR EWMA Threshold Counts(signed)

EGR EWMA Counts(signed)

EGR Pintle Position Error Counts(signed)

Engine Run Time Seconds Varies (Since start up)

BPW Bank 1 mS 0–999.9

Air Fuel Ratio Ratio 14.6:1 (Varies)

Spark Degrees Varies

MAP kPa 25–35 kPa

BARO kPa 65–100 kPa (varies with altitude andwith the BARO pressure)

Calculated Load % 0–100

Vehicle Speed mph 0

1F – 8IENGINE CONTROLS

DAEWOO V–121 BL4

Oxygen Sensor Data Display

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data

Engine Speed RPM µ100 rpm from the Desired rpm

Engine Run Time Seconds Varies (Since start up)

Loop Status Open/Closed Closed

O2S Bank 1 Sensor 1 mV 0–1132

O2S Bank 1 Sensor 1 Not Ready, Ready Ready

Rich/Lean Bank 1 Lean, Rich –

Injector Pulse Bank 1 mS Varies

Start Up Coolant Temperature C – F 4³–34³C (39³–93³F) Varies with theunderhood temperature when start-

ing

Engine Coolant Temperature C – F 85³–115³C (185³–239³F) Varieswith the coolant temperature

Start Up Intake Air Temperature C – F 12³–42³C (54³–108³F) Varies withthe underhood temperature when

starting

Intake Air Temperature C – F Varies with the underhood tempera-ture

O2S Time to Activity Bank 1 Sensor1

Seconds Varies

Short Term FT Bank 1 % –100 to 100 (Varies)

Long Term FT Bank 1 % –100 to 100 (Varies)

TP Angle % 0% (up to 100% at wide openthrottle)

Calculated Air Flow g/sec Varies

MAP kPa 25–35 kPa

EVAP Purge PWM % 0–100

Ignition 1 Volts 12.0–15.0

Air Fuel Ratio Ratio 14.6:1 (Varies)

Decel Fuel Mode Inactive/Active –

Power Enrichment Inactive/Active –

O2S Warm Up Time Bank 1 – Senor1

Seconds Varies

HO2S Bank 1 Sensor 2 mV 0–1000 and varying

ENGINE CONTROLS 1F – 9

DAEWOO V–121 BL4

Misfire Data Display

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data

Misfire Current #1 0–255 counts 0 (increase with a misfire)

Misfire History #1 0–255 counts 0 (increase with a misfire)

Misfire Current #2 0–255 counts 0 (increase with a misfire)

Misfire History #2 0–255 counts 0 (increase with a misfire)

Misfire Current #3 0–255 counts 0 (increase with a misfire)

Misfire History #3 0–255 counts 0 (increase with a misfire)

Misfire Current #4 0–255 counts 0 (increase with a misfire)

Misfire History #4 0–255 counts 0 (increase with a misfire)

Misfire Failures First Fail 0–255 counts 0 (increase with a misfire)

Misfire Passes First Fail 0–255 counts 0 (increase with a misfire)

Total Misfire Current Count 0–255 counts 0 (increase with a misfire)

Weak Cylinder –

Engine Speed RPM µ100 rpm from the Desired RPM

TP Angle % 0% (up to 100% at wide openthrottle)

Calculated Load % 0–100

Engine Coolant Temperature CF 85³–115³C(185³–239³F) Varies withthe coolant temperature

Intake Air Temperature CF 10³–80³C(50³–176³F) Varies withthe underhood temperature

Cam Active Counter Counts 0–255

Spark Advance Degrees Varies

G Sensor Volts –

EGR Desired Position % 0%

EGR Actual Position % 0%

MAP kPa 25–35 kPa

Vehicle Speed mph 0

Air Conditioning Request On/Off Off

Air Conditioning Clutch On/Off Off

Knock Active Counter Counts 0–255

Knock Retard Degrees Varies

Decel Fuel Mode Yes/No –

Power Enrichment Mode Yes/No –

Injector Pulse Bank 1 mS Varies

O2S Bank 1 Sensor 1 mV 0–1000 and varying

HO2S Bank 1 Sensor 2 mV 0–1000 and varying

Short Term FT Bank 1 % –100 to 100 (Varies)

Long Term FT Bank 1 % –100 to 100 (Varies)

1F – 10IENGINE CONTROLS

DAEWOO V–121 BL4

TEC Display Table

At idle / Upper Radiator / Closed Throttle / Park or Neutral / Closed loop / Acc. OFF

Scan Tool Parameter Units Displayed Typical Data

Engine Speed RPM µ100 rpm from the Desired RPM

TP Angle % 0 (up to 100% at wide open throttle)

Engine Coolant Temperature C,F 85³–115³C (185³–239³F) Varieswith the coolant temperature

Intake Air Temperature C,F 10³–80³C(50³–176³F) Varies withthe underhood temperature

Cam Active Counter Counts 0–255

Spark Degrees Varies

MAP kPa 25–35 kPa

Vehicle Speed mph 0

Decel Fuel Mode Yes/No –

Power Enrichment Mode Yes/No –

Injector Pulse Bank 1 mS Varies

Crank Error Latched Yes/No –

Sum Out Of Range Yes/No –

Opposing Factor Out Of Range Yes/No –

Factor Out Of Range Yes/No –

Enable Criteria Not Met Yes/No –

Cat Damaging Misfire Yes/No –

Test is Running Yes/No –

Learned This Key Cycle Yes/No –

Attempts to Learn Counts

ENGINE DATA DISPLAY TABLEDEFINITIONS

PCM/ECM Data Description

The following information will assist in diagnosing emis-sion or driveability problems. A first technician can viewthe displays while the vehicle is being driven by secondtechnician. Refer to Powertrain On–Board Diagnostic(OBD II) System Check for additional information.

A/C Clutch

The A/C Relay represents the commanded state of theA/C clutch control relay. The A/C clutch should be en-gaged when the scan tool displays ON.

A/C Pressure

The A/C High Side displays the pressure value of the A/Crefrigerant pressure sensor. The A/C High Side helps todiagnose the diagnostic trouble code (DTC) P0533.

A/C Request

The A/C Request represents whether the air conditioningis being requested from the HVAC selector. The input is re-ceived by the instrument panel cluster and then sent overuniversal asynchronous receiver transmitter (UART) seri-al data to the powertrain control module (PCM)/enginecontrol module (ECM) and finally to the scan tool overclass 2 serial data.

Air Fuel Ratio

The Air Fuel Ration indicates the air to fuel ratio based onthe Oxygen Sensor (O2S 1) inputs. The PCM/ECM usesthe fuel trims to adjust fueling in order to attempt to main-tain an air fuel ratio of 14.7:1.

BARO

The Barometric Pressure (BARO) sensor measures thechange in the intake manifold pressure which results fromaltitude changes. This value is updated at ignition ON andalso at Wide Open Throttle (WOT).

ENGINE CONTROLS 1F – 11

DAEWOO V–121 BL4

BPW Bank 1

Indicates the base Pulse Width Modulation (PWM) or ONtime of the indicated cylinder injector in milliseconds.When the engine load is increased, the injector pulse widthwill increase.

Calculated Air Flow

The calculated air flow is a calculation based on manifoldabsolute pressure. The calculation is used in several diag-nostics to determine when to run the diagnostics.

Calculated Load

Indicates engine load based on Manifold Absolute Pres-sure (MAP). The higher the percentage, the more load theengine is under.

Camshaft Activity CounterThe Camshaft Position (CMP) activity counter displaysthe activity sent to the PCM/ECM from the CMP sensor.The counter will continually increment while the engine isrunning. The CMP activity counter is helpful in diagnosingDTC P0342.

Desired IdleThe PCM/ECM commands the idle speed. The PCM/ECMcompensates for various engine loads in order to maintainthe desired idle speed. The actual engine speed should re-main close to the desired idle under the various engineloads with the engine idling.

Engine Coolant TemperatureThe Engine Coolant Temperature (ECT) sensor sends en-gine temperature information to the PCM/ECM. The PCM/ECM supplies 5 volts to the engine coolant temperaturesensor circuit. The sensor is a thermistor which changesinternal resistance as temperature changes. When thesensor is cold (internal resistance high), the PCM/ECMmonitors a high voltage which it interprets as a cold en-gine. As the sensor warms (internal resistance de-creases), the voltage signal will decrease and the PCM/ECM will interpret the lower voltage as a warm engine.

EGR Desired Position

The desired exhaust gas recirculation (EGR) position isthe commanded EGR position. The PCM/ECM calculatesthe desired EGR position. The higher the percentage, thelonger the PCM/ECM is commanding the EGR valve ON.

Engine Run TimeThe engine run time is a measure of how long the enginehas been running. When the engine stops running, the tim-er resets to zero.

Engine SpeedEngine Speed is computed by the PCM/ECM from the fuelcontrol reference input. It should remain close to desiredidle under the various engine loads with the engine idling.

EVAP PurgeThe Evaporative (EVAP) Emission purge valve solenoid isa proportional signal used in order to control the EVAPcanister purge function. At 0% the valve is commandedfully closed. 100% implies that the valve is fully open.

EVAP Purge SolenoidWhen energized, the EVAP Emission Canister Purge So-lenoid allows the fuel vapor to flow from the EVAP Canisterto the engine. The EVAP Emission Canister Purge Sole-noid is normally closed. The EVAP Emission CanisterPurge Solenoid is pulse width modulated by the PCM/ECM. The EVAP Emission Canister Purge Solenoid reads0% when closed and 100% when fully opened.

EVAP Vent SolenoidThe EVAP Emission Vent Solenoid allows fresh outside airto the EVAP Emission Canister during purge mode. TheEVAP Emission Vent Solenoid allows the diagnostic to pulla vacuum on the fuel tank by closing the vent solenoid.

FanThe Fan Control (FC) Relay is commanded by the PCM/ECM. The FC Relay displays the command as ON or OFF.

Fuel Level SensorThe Fuel Level Sensor monitors the fuel level in the tank.The Fuel Level Sensor monitors the rate of change of theair pressure in the EVAP Emission Canister Purge Sys-tem. Several of the Enhanced EVAP Emission CanisterPurge System diagnostics are dependent upon the correctfuel level.

Fuel Tank Pressure SensorThe fuel tank pressure sensor measures the differencebetween the pressure or the vacuum in the fuel tank andthe outside air pressure. When the air pressure in the fueltank equals the outside air pressure, the output voltage ofthe sensor is 1.3 to 1.7 volts.

IAC PositionThe scan tool displays the PCM/ECM command for theIdle Air Control (IAC) pintle position in counts. The higherthe number of counts, the greater the commanded idlespeed reads. The Idle Air Control responds to changes inthe engine load in order to maintain the desired idle rpm.

Intake Air TemperatureThe PCM/ECM converts the resistance of the Intake Airemperature (IAT) sensor to degrees in the same manneras the ECT sensor. Intake air temperature is used by thePCM/ECM to adjust fuel delivery and spark timing accord-ing to incoming air density.

Ignition 1 (Voltage)The ignition volts represent the system voltage measuredy the PCM/ECM at the ignition feed circuit.

Knock RetardThe Knock Sensor (KS) Retard indicates the amount ofpark advance the PCM/ECM is decreasing in response othe KS signal.

1F – 12IENGINE CONTROLS

DAEWOO V–121 BL4

Knock PresentThe KS Noise Channel indicates when the PCM/ECMetects the KS signal. The PCM/ECM should display O atidle.

Long Term FTThe Long Term Fuel Trim (FT) is derived from the shortterm fuel trim value. The Long Term FT is used for the longterm correction of the fuel delivery. A value of 128 counts(0%) indicates that the fuel delivery requires no com-pensation in order to maintain a 14.7:1 air to fuel ratio. Avalue below 128 counts means that the fuel system is toorich and the fuel delivery is being reduced. The PCM/ECMis decreasing the injector pulse width. A value above 128counts indicates that a lean condition exists for which thePCM/ECM is compensating.

Long Term FT AverageLong Term FT Average is derived from the long term fueltrim from all of the cells. The PCM/ECM then takes all ofthe values and then creates one average value.

Loop StatusThe Closed Loop is displayed indicating that the PCM/ECM is controlling the fuel delivery according to the Oxy-gen Sensor (O2S 1) voltage as close to an air/fuel ratio of14.7 to 1 as possible.

MAPThe MAP sensor measures the change in the intake man-ifold pressure which results from engine load and speedchanges. As the intake manifold pressure increases, theair density in the intake also increases and the additionalfuel is required.

Misfire Current #1–4Indicates the number of current misfires that are presentin the indicated cylinder. Increments only when misfire iscurrent.

Misfire History #1–4Indicates the number of misfires that have occurred after195 current misfires have been counted. The current mis-fire counter will add its misfires to the history misfire count-er after 195 total misfires have taken place. If 1 cylinder ismisfiring, the misfiring current counter will have 195 mis-fires counted before adding to its history counter. If 2 cylin-ders are misfiring, the misfiring current counter will add totheir history counters after 97 misfires. The counter incre-ments only after a misfire diagnostic trouble code (DTC)has been set.

Oxygen Sensor Bank 1 Sensor 1The pre–converter Oxygen Sensor (O2S 1) reading repre-sents the exhaust oxygen sensor output voltage. This volt-age will fluctuate constantly between 100 mv (lean ex-haust) and 900 mv (rich exhaust) when the system isoperating in a Closed Loop.

Oxygen Sensor Bank 1 Sensor 2The post–converter Heated Oxygen Sensor (HO2S 2)represents the exhaust oxygen output voltage past thecatalytic converter. This voltage remains inactive, or thevoltage will appear lazy within a range of 100 mv (lean ex-haust) and 900 mv (rich exhaust) when operating in aClosed Loop.

Short Term FTThe Short Term FT represents a short term correction tofuel delivery by the PCM/ECM in response to the amountof time the oxygen sensor voltage spends above or belowthe 450 mv threshold. If the oxygen sensor has mainlybeen below 450 mv, indicating a lean air/fuel mixture, shortterm fuel trim will increase to tell the PCM/ECM to add fuel.If the oxygen sensor voltage stays mainly above thethreshold, the PCM/ECM will reduce fuel delivery to com-pensate for the indicated rich condition.

Short Term FT AverageThe Short Term FT Average is derived from the short termfuel trim from all of the cells. The PCM/ECM takes all of thevalues and then creates one average value.

SparkThis is a display of the spark advance Ignition Coil (IC) cal-culation which the PCM/ECM is programming in the igni-tion system. It computes the desired spark advance usingdata such as engine temperature, rpm, engine load, ve-hicle speed and operating mode.

TCC Brake SwitchWhen the brake pedal is applied, the Torque ConverterClutch (TCC) brake switch sends a signal to the PCM/ECM to disengage the TCC and disable the cruise control.

Total Misfire Current CounterIndicates the total number of misfires that have been de-tected in all the cylinders after 100 engine cycles. Onecycle equals one complete 4 stroke cycle. The total misfireonly increments during the steady state cruise conditions.

TP AngleFrom the Throttle Position (TP) Sensor voltage input, thePCM/ECM computes the TP. The TP Angle will auto zeroto 0% at idle (TP voltage below 0.90 volts). The TP Anglewill read 100% at WOT.

TP SensorThe PCM/ECM uses the TP Sensor in order to determinethe amount of the throttle demanded by the vehicle’s oper-ator. The TP Sensor reads between 0.36–0.96 volts at idleto above 4 volts at WOT.

Vehicle SpeedThe vehicle speed sensor signal is converted into mph orkm/h for display. The vehicle speed output from the PCM/ECM is 4000 pulses per mile. The scan tool uses the class2 serial data from the PCM/ECM to obtain vehicle speed,

ENGINE CONTROLS 1F – 13

DAEWOO V–121 BL4

while the Instrument Panel Cluster (IPC), cruise controlmodule and the chime alarm module use the 4000 ppmoutput.

FASTENER TIGHTENING SPECIFICATIONS

Application Nm Lb–Ft Lb–In

Accessory Mounting Bracket Bolts 35 26 –

Camshaft Position Sensor Bolts 12 – 106

Crankshaft Position Sensor Retaining Bolt 10 – 89

Electronic Ignition System Ignition Coil Retaining Bolts 10 – 89

Engine Coolant Temperature Sensor 25 18 –

Evaporative Emission Canister Flange Bolt 20 15 –

Evaporative Emission Canister Protective Cover 8 – 71

Evaporative Emission Canister Purge Solenoid Bracket Bolt 5 – 44

Exhaust Gas Recirculation Valve Retaining Bolts 20 15 –

Fuel Cutoff Switch Mounting Bolts 3 – 27

Fuel Filter Mounting Bracket Assembly Bolt 10 – 89

Fuel Pressure Regulator Retaining Screw 12 – 106

Fuel Rail Retaining Bolts 25 18 –

Fuel Tank Strap Retaining Nuts 13 – 115

Heated Oxygen Sensor 41 30 –

Idle Air Control Valve Retaining Bolts 3 – 27

Knock Sensor Bolt 20 15 –

Manifold Absolute Pressure Sensor Mounting Bracket Nuts 10 – 89

Manifold Absolute Pressure Sensor Retaining Bolts and Nuts 10 – 89

Oxygen Sensor 41 30 –

Rear A/C Compressor Mounting Bracket Bolts 35 26 –

Spark Plug Cover Bolts 3 – 27

Throttle Body Retaining Nuts 9 – 80

Throttle Position Sensor Retaining Bolts 2 – 18

1F – 14IENGINE CONTROLS

DAEWOO V–121 BL4

FUEL SYSTEM SPECIFICATIONSGasolineAll engines are designed to use unleaded fuel only. Un-leaded fuel must be used for proper emission control sys-tem operation. Its use will also minimize spark plug foulingand extend engine oil life. Using leaded fuel can damagethe emission warranty coverage. The fuel should meetspecification ASTM D4814 for the U.S. or CGSB 3.5 M93for Canada. All engines are designed to use unleaded fuelwith a minimum U(R+M)/2e (pump) octane number of 87,where R=research octane number, and M=motor octanenumber.

EthanolYou may use fuel containing ethanol (ethyl alcohol) orgrain alcohol providing that there is not more than 10 per-cent ethyl alcohol by volume.

MethanolDo not use fuels containing methanol. Methanol can cor-rode metal parts and also cause damage to plastic andrubber parts in the fuel system.

Methyl Tertiary–Butyl Ether (MTBE)You may use fuel containing Methyl Tertiary–Butyl Ether(MTBE) providing there is not more than 15 percent MTBEby volume.

TEMPERATURE VS RESISTANCE³C ³F OHMS

Temperature vs Resistance Values (Approximate)

100 212 177

90 194 241

80 176 332

70 158 467

60 140 667

50 122 973

45 113 1188

40 104 1459

35 95 1802

30 86 2238

25 77 2796

20 68 3520

15 59 4450

10 50 5670

5 41 7280

0 32 9420

–5 23 12300

–10 14 16180

–15 5 21450

–20 –4 28680

–30 –22 52700

–40 –40 100700

ENGINE CONTROLS 1F – 15

DAEWOO V–121 BL4

SCHEMATIC AND ROUTING DIAGRAMS

PCM/ECM WIRING DIAGRAM (1 OF 6)(IPCM–6KD/ISFI–6TD)

1F – 16IENGINE CONTROLS

DAEWOO V–121 BL4

PCM/ECM WIRING DIAGRAM (2 OF 6)(IPCM–6KD/ISFI–6TD)

ENGINE CONTROLS 1F – 17

DAEWOO V–121 BL4

PCM/ECM WIRING DIAGRAM (3 OF 6)(IPCM–6KD/ISFI–6TD)

1F – 18IENGINE CONTROLS

DAEWOO V–121 BL4

PCM/ECM WIRING DIAGRAM (4 OF 6)(IPCM–6KD/ISFI–6TD)

ENGINE CONTROLS 1F – 19

DAEWOO V–121 BL4

PCM/ECM WIRING DIAGRAM (5 OF 6)(IPCM–6KD/ISFI–6TD)

1F – 20IENGINE CONTROLS

DAEWOO V–121 BL4

PCM/ECM WIRING DIAGRAM (6 OF 6)(IPCM–6KD/ISFI–6TD)

ENGINE CONTROLS 1F – 21

DAEWOO V–121 BL4

CONNECTOR END VIEW

1F – 22IENGINE CONTROLS

DAEWOO V–121 BL4

ENGINE CONTROLS 1F – 23

DAEWOO V–121 BL4

1F – 24IENGINE CONTROLS

DAEWOO V–121 BL4

ENGINE CONTROLS 1F – 25

DAEWOO V–121 BL4

1F – 26IENGINE CONTROLS

DAEWOO V–121 BL4

COMPONENT LOCATOR

ENGINE CONTROLS 1F – 27

DAEWOO V–121 BL4

Components on PCM/ECM Harness

11. Powertrain Control Module (PCM)/Engine ControlModule (ECM)

12. Data Link Connector (DLC)13. Service Reminder Indicator Lamp/Malfunction Indi-

cator Lamp14. PCM/ECM/ABS Harness Ground15. Fuse Panel (2)

PCM/ECM Controlled Devices

19. Exhaust Gas Recirculation (EGR) Valve21. Fuel Injector (4)22. Idle Air Control (IAC) Valve23. Fuel Pump Relay24. Cooling Fan Relays25. Series/Parallel Cooling Fan Relay (A/C Only)26. Electronic Ignition (EI) System Ignition Coil27. Evaporative Emission (EVAP) Controlled Canister

Purge Solenoid28. Ignition 1 Relay29. A/C Compressor Relay

30. Variable Geometry Induction System (VGIS)

Information Sensors

31. Manifold Absolute Pressure (MAP) Sensor32. Pre–Converter Oxygen Sensor (O2S 1)33. Throttle Position (TP) Sensor34. Engine Coolant Temperature (ECT) Sensor35. Intake Air Temperature (IAT) Sensor36. Vehicle Speed Sensor (VSS)37. P/N Position Switch (Automatic Transaxle only)38. Crankshaft Position (CKP) Sensor39. Knock Sensor40. Post–Converter Oxygen (HO2S 2) Sensor41. Camshaft Position (CMP) Sensor

PCM/Not ECM Connected

42. Evaporative Emission Canister (under vehicle, be-hind right rear wheel)

43. Oil Pressure Switch44. Air Cleaner

1F – 28IENGINE CONTROLS

DAEWOO V–121 BL4

DIAGNOSIS

SYSTEM DIAGNOSIS

DIAGNOSTIC AIDSIf an intermittent problem is evident, follow the guidelinesbelow.

Preliminary ChecksBefore using this section you should have already per-formed the ”On–Board Diagnostic System Check.”

Perform a thorough visual inspection. This inspection canoften lead to correcting a problem without further checksand can save valuable time. Inspect for the following con-ditions:

Powertrain control module (PCM)/engine controlmodule (PCM/ECM) grounds for being clean, tight,and in their proper location.

Vacuum hoses for splits, kinks, collapsing and prop-er connections as shown on the Vehicle EmissionControl Information label. Inspect thoroughly forany type of leak or restriction.

Air leaks at the throttle body mounting area and theintake manifold sealing surfaces.

Ignition wires for cracks, hardness, proper routing,and carbon tracking.

Wiring for proper connections. Wiring for pinches or cuts.

Diagnostic Trouble Code TablesDo not use the diagnostic trouble code (DTC) tables to tryto correct an intermittent fault. The fault must be presentto locate the problem.

Incorrect use of the DTC tables may result in the unneces-sary replacement of parts.

Faulty Electrical Connections or WiringMost intermittent problems are caused by faulty electricalconnections or wiring. Perform a careful inspection of sus-pect circuits for the following:

Poor mating of the connector halves. Terminals not fully seated in the connector body. Improperly formed or damaged terminals. All con-

nector terminals in a problem circuit should be care-fully inspected, reformed, or replaced to insure con-tact tension.

Poor terminal–to–wire connection. This requiresremoving the terminal from the connector body.

Road TestIf a visual inspection does not find the cause of the prob-lem, the vehicle can be driven with a voltmeter or a scantool connected to a suspected circuit. An abnormal voltageor scan tool reading will indicate that the problem is in thatcircuit.

If there are no wiring or connector problems found and aDTC was stored for a circuit having a sensor, except forDTC P0171 and DTC P0172, replace the sensor.

Intermittent Service Reminder Indicator (SRI) LampAn intermittent service reminder indicator (SRI) lamp withno DTC present may be caused by the following:

Electrical system interference caused by a defec-tive relay, PCM/ECM driven solenoid, or switch.

Improper installation of electrical options such aslights, two–way radios, sound systems, or securitysystems.

Ignition control wires should be routed away fromignition wires, ignition system components, and thegenerator.

Ignition secondary wires shorted to ground. SRI lamp driver wire or diagnostic test terminal in-

termittently shorted to ground. Intermittent lose of PCM/ECM ground connections.

Fuel SystemSome intermittent driveability problems can be attributedto poor fuel quality. If a vehicle is occasionally runningrough, stalling, or otherwise performing badly, ask the cus-tomer about the following fuel buying habits:

Do they always buy from the same source? If so,fuel quality problems can usually be discounted.

Do they buy their fuel from whichever fuel stationthat is advertising the lowest price? If so, check thefuel tank forsigns of debris, water, orotherconta-mination.

IDLE LEARN PROCEDUREWhenever the battery cables, the powetrain control mod-ule (PCM)/engine control module (PCM/ECM), or thePCM/ECM fuse is disconnected or replaced, the followingidle learn procedure must be performed:

1. Turn the ignition ON for 5 seconds.2. Turn the ignition OFF for 5 seconds.3. Turn the ignition ON for 5 seconds.4. Start the engine in park/neutral.5. Allow the engine run until the engine coolant is

above 85C (185F).6. Turn the A/C ON for 10 seconds, if equipped.7. Turn the A/C OFF for 10 seconds, if equipped.8. If the vehicle is equipped with an automatic trans-

axle, apply the parking brake. While pressing thebrake pedal, place the transaxle in D (drive).

9. Turn the A/C ON for 10 seconds, if equipped.10. Turn the A/C OFF for 10 seconds, if equipped.11. Turn the ignition OFF. The idle learn procedure is

complete.

ENGINE CONTROLS 1F – 29

DAEWOO V–121 BL4

ON–BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK

Circuit Description

The On–Board Diagnostic (OBD II) System Check is thestarting point for any driveability complaint diagnosis. Be-fore using this procedure, perform a careful visual/physi-cal check of the powertrain control module (PCM)/enginecontrol module (ECM) and the engine grounds for cleanli-ness and tightness.

The OBD II System Check is an organized approach toidentifying a problem created by an electronic engine con-trol system malfunction.

Diagnostic Aids

An intermittent may be caused by a poor connection,rubbed–through wire insulation or a wire broken inside theinsulation. Check for poor connections or a damaged har-ness. Inspect the PCM/ECM harness and connections forimproper mating, broken locks, improperly formed or dam-aged terminals, poor terminal–to–wire connection, anddamaged harness.

Test DescriptionNumbers below refer to the step number on the DiagnosticChart:

1. The Malfunction Indicator Lamp (MIL) should beON steady with the ignition ON and the engineOFF. If not, go to ”Diagnostic Aids”.

2. Checks the Class 2 data circuit and ensures thatthe PCM/ECM is able to transmit serial data.

3. This test ensures that the PCM/ECM is capable ofcontrolling the MIL and the MIL driver circuit is notshorted to ground.

4. If the engine will not start, refer to ”Engine CranksBut Will Not Run” in this section.

7. A scan tool parameter which is not within the typicalrange may help to isolate the area which is causingthe problem.

10. This vehicle is equipped with a PCM/ECM whichutilizes an electrically erasable programmable readonly memory (EEPROM). The replacement PCM/ECM must be programmed. Refer to the latestTechline procedure for PCM/ECM reprogramming.

1F – 30IENGINE CONTROLS

DAEWOO V–121 BL4

On–Board Diagnostic (OBD II) System Check

Step Action Value(s) Yes No

1 1. Ignition ON, engine OFF.2. Observe the malfunction indicator lamp (MIL)Is the MIL on?

Go to Step 2 Go to ”No Mal-function Indica-

tor Lamp”

2 1. Ignition OFF.2. Install the scan tool.3. Ignition ON.4. Attempt to display the powertrain control mod-

ule (PCM)/engine control module (ECM) en-gine data with the scan tool.

Does the scan tool display the PCM/ECM enginedata?

Go to Step 3 Go to Step 8

3 1. Using the scan tool output test function, selectMIL dash lamp control and command the MILOFF.

2. Observe the MIL.Does the MIL turn OFF?

Go to Step 4 Go to ”Malfunc-tion Indicator

Lamp onSteady”

4 Attempt to start the engine.Does the engine start and continue to run?

Go to Step 5 Go to ”EngineCranks But Will

Not Run”

5 Select DISPLAY DTC with the scan tool.Are any Diagnostic Trouble Codes (DTCs) stored?

Go to Step 6 Go to Step 7

6 Check the display for DTCs P0107, P0108, P0113,P0118, P0122, P0123, P0712, P1392.Are two or more of the following DTCs stored?

Go to ”MultiplePCM/ECM In-formation Sen-sor DTCs Set”

Go to applica-ble DTC table

7 Compare the PCM/ECM data values displayed onthe scan tool to the typical engine scan data values.Are the displayed values normal or close to the typi-cal values?

Go to ”PCM/ECM OutputDiagnosis”

Go to indicatedcomponent

system check

8 1. Ignition OFF, disconnect the PCM/ECM.2. Ignition ON, engine OFF.3. Check the class 2 data circuit for an open,

short to ground, or short to voltage. Also,check the Data Link Connector (DLC) ignitionfeed circuit for an open or short to ground andthe DLC ground circuits for an open.

Is a problem found?

Go to Step 9 Go to Step 10

9 Repair the open, short to ground or short to voltagein the class 2 data circuit or the DLC ignition feed cir-cuit or DLC ground circuts.Is the repair complete?

System OK

10 1. Attempt to reprogram the PCM/ECM.2. Attempt to display the PCM/ECM data with the

scan tool.Does the scan tool display PCM/ECM engine data?

Go to Step 2 Go to Step 11

11 Replace the PCM/ECM.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 31

DAEWOO V–121 BL4

PCM/ECM OUTPUT DIAGNOSISCircuit DescriptionThe powertrain control module (PCM)/engine controlmodule (ECM) controls most components with electronicswitches which complete a ground circuit when turned on.These switches are arranged in groups of 4 and 7, and arecalled either a surface mounted quad driver module, whichcan independently control up to 4 output terminals or anOutput Driver Module (ODM), which can independentlycontrol up to 7 outputs. Not all of the outputs are alwaysused.

Drivers are fault protected. If a relay or solenoid is shorted,having very low or zero resistance, or if the control side ofthe circuit is shorted to voltage, it would allow too muchcurrent flow into the PCM/ECM. The driver senses thisand the output is turned OFF or its internal resistance in-creases to limit current flow and protect the PCM/ECMand driver. The result is high output terminal voltage whenit should be low. If the circuit from B+ to the component orthe component is open, or the control side of the circuit isshorted to ground, terminal voltage will be low. Either ofthese conditions is considered to be a driver fault.

Drivers also have a fault line to indicate the presence of acurrent fault to the PCM/ECM’s central processor. A scantool displays the status of the driver fault lines as 0=OKand 1=Fault.

Diagnostic AidsThe scan tool has the ability to command certain compo-nents and functions ON and OFF. If a component or func-tion does not have this capability, operate the vehicle dur-ing its normal function criteria to check for an open orshorted circuit.

An open or short to ground will appear in the open posi-tions on the scan tool only when it is not commanded bythe PCM/ECM or the scan tool, while a short to voltage willappear in the short positions on the scan tool only while thecomponent is being commanded by the PCM/ECM orscan tool.

Test Description

Number(s) below refer to the step number(s) on the Diag-nostic Table.

1. The Powertrain On–Board Diagnostic (OBD II) Sys-tem Check prompts the technician to completesome basic checks and store the freeze frame andfailure records data on the scan tool if applicable.This creates an electronic copy of the data takenwhen the malfunction occurred. The information isthen stored on the scan tool for later reference.

2. A 1 in any of the positions indicates that an open orshort is present in the corresponding circuit for thatposition.

4. An open or short to ground will appear in the openpositions on the scan tool only when it is not com-manded by the PCM/ECM or scan tool, while ashort to voltage will appear in the short positions onthe scan tool only while the component is beingcommanded by the PCM/ECM or scan tool.

5. Proper operation of any component of function withno 1 in any operation of the positions indicates thatsystem operation is normal at this time.

6. A component or function that failed to operate atthis point indicates that the fault is not on the PCM/ECM side of the circuitry.

8. The 1 going away after disconnecting the compo-nent electrical connector indicates that the compo-nent or component side wiring is at fault. If the scantool indicates a fault after disconnecting the compo-nent electrical connector and verifying that no openor short is present in the circuit, then the PCM/ECMis faulty.

9. The replacement PCM/ECM must be repro-grammed. Refer to the latest Techline procedure forPCM/ECM reprogramming.

10. If no faults have been found at this point, refer to”Diagnostic Aids” in this section for additionalchecks and information.

1F – 32IENGINE CONTROLS

DAEWOO V–121 BL4

PCM/ECM Output Diagnosis

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the check performed ?

Go to Step 2 Go to ”On–Board Diagnos-

tic SystemCheck”

2 Install the scan tool.Is there a number 1 below any of the numbered posi-tions in the OUTPUT DRIVERS?

Go to Step 3 Go to Step 4

3 Check for an open or shorted circuit in any corre-sponding position (circuit) that contained a number1 and repair as necessary.Is a repair necessary?

Go to Step 10 Go to Step 8

4 Command the output being checked with a scan toolwhile watching the corresponding position for eachcircuit.Do any of the positions change to a 1?

Go to Step 7 Go to Step 5

5 Command the output being checked with a scan toolwhile watching the corresponding position for eachcircuit.Does the component or function operate when com-manded?

Go to Step 10 Go to the ap-propriate com-ponent repair

6 Repair the short to voltage in the corresponding cir-cuit for position (circuit) that displayed a 1.Is the repair complete?

Go to Step 10

7 Disconnect the electrical connector to the compo-nent connected to the faulty circuit.Is a 1 still displayed in the corresponding OUTPUTDRIVER position?

Go to Step 9 Go to the ap-propriate com-ponent repair

8 Replace the powertrain control module (PCM)/en-gine control module (ECM)Is the repair complete?

Go to Step 10

9 Operate the vehicle within the conditions underwhich the original symptom was noted.Does the system now operate properly?

System OK Go to Step 2

ENGINE CONTROLS 1F – 33

DAEWOO V–121 BL4

MULTIPLE PCM/ECM INFORMATION SENSOR DTCS SETCircuit DescriptionThe powertrain control module (PCM)/engine controlmodule (ECM) monitors various sensors to determine en-gine operating conditions. The PCM/ECM controls fuel de-livery, spark advance, transaxle operation, and emissioncontrol device operation based on the sensor inputs.

The PCM/ECM provides a sensor ground to all of the sen-sors. The PCM/ECM applies 5 volts through a pullup resis-tor and monitors the voltage present between the sensorand the resistor to determine the status of the EngineCoolant Temperature (ECT) sensor, the Intake Air Tem-perature (IAT) sensor, and the Transmission Fluid Tem-perature (TFT) sensor. The PCM/ECM provides the Ex-haust Gas Recirculation (EGR) Pintle Position Sensor, theThrottle Position (TP) sensor, the Manifold Absolute Pres-sure (MAP) sensor, the Air Conditioning Temperature(ACT) sensor and the Fuel Tank Pressure Sensor with a5 volt reference and a sensor ground signal. The PCM/ECM monitors the separate feedback signals from thesesensors to determine their operating status.

Diagnostic AidsBe sure to inspect PCM/ECM and engine grounds for be-ing secure and clean.

A short to voltage in one of the sensor circuits can causeone or more of the following Diagnostic Trouble Codes(DTCs) to be set: P0108, P0113, P0118, P0123, P1106,P1111, P1115, P1121, P1625.

If a sensor input circuit has been shorted to voltage, en-sure that the sensor is not damaged. A damaged sensorwill continue to indicate a high or low voltage after the af-fected circuit has been repaired. If the sensor has beendamaged, replace it.

An open in the sensor ground circuit between the PCM/ECM and the splice will cause one or more of the followingDTCs to be set: P0108, P0113, P0118, P0123, P1106,P1111, P1115, P1121.

A short to ground in the 5 volt reference circuit or an openin the 5 volt reference circuit between the PCM/ECM andthe splice will cause one or more of the following DTCs tobe set: P0107, P0112, P0117, P0122, P1107, P1112,P1114, P1122.

Check for the following conditions:

Inspect for a poor connection at the PCM/ECM.Inspect harness connectors for backed–out termi-nals, improper mating, broken locks, improperlyformed or damaged terminals, and poor terminal–to–wire connection.

Inspect the wiring harness for damage. If the har-ness appears to be OK, observe an affected sen-sor’s displayed value on the scan tool with the igni-tion ON and the engine OFF while movingconnectors and wiring harnesses related to the af-fected sensors. A change in the affected sensor’sdisplayed value will indicate the location of the fault.

Test Description

Number(s) below refer to the step number(s) on the Diag-nostic Table.

1. The Powertrain On–Board Diagnostic (OBD II) Sys-tem Check prompts the technician to completesome basic checks and store the freeze frame andfailure records data on the scan tool if applicable.This creates an electronic copy of the data takenwhen the malfunction occurred. The information isthen stored on the scan tool for later reference.

9. A faulty EGR valve can leak a small amount of cur-rent from the ignition feed circuit to the 5 volt refer-ence circuit. If the problem does not exist with theEGR valve disconnected, replace the EGR valve.

0. If a sensor input circuit has been shorted to voltage,ensure that the sensor has not been damaged. Adamaged IAT or ECT sensor will continue to indi-cate a high voltage or low temperature after theaffected circuit has been repaired. A damaged ACT,TP, MAP, Fuel Tank Pressure, or EGR Pintle Posi-tion sensor will indicate a high or low voltage ormay be stuck at a fixed value after the affected cir-cuit has been repaired. If the sensor has been dam-aged, replace it.

21. The replacement PCM/ECM must be repro-grammed. Refer to the latest Techline procedure forPCM/ECM reprogramming.

1F – 34IENGINE CONTROLS

DAEWOO V–121 BL4

Multiple PCM/ECM Information Sensor DTCs Set

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the system check complete?

Go to Step 2 Go to ”On–Board Diagnos-

tic SystemCheck”

2 1. Ignition OFF, disconnect the powertrain controlmodule (PCM)/engine control module (ECM).

2. Ignition ON, check the 5 volt reference circuitfor the following conditions:

Poor connection at the PCM/ECM. Open between the PCM/ECM connector

affected sensors shorted to ground or volt-age.

3. If a problem is found, locate and repair theopen or short circuit as necessary.

Is a problem found?

Go to Step 21 Go to Step 3

3 1. Check the sensor ground circuit for the follow-ing conditions:

Poor connection at the PCM/ECM or af-fected sensors.

Open between the PCM/ECM connectorand the affected sensors.

2. If a problem is found, repair it as necessary.Is a problem found?

Go to Step 21 Go to Step 4

4 Measure the voltage between the Exhaust Gas Re-circulation (EGR) Pintle Position Sensor signal cir-cuit at the PCM/ECM harness connector andground.Does the voltage measure near the specified value?

0 v Go to Step 5 Go to Step 9

5 Measure the voltage between the Manifold AbsolutePressure (MAP) sensor signal circuit and the PCM/ECM harness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 6 Go to Step 12

6 Measure the voltage between the Throttle Position(TP) sensor signal circuit and the PCM/ECM har-ness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 7 Go to Step 13

7 Measure the voltage between the Intake Air Temper-ature (IAT) sensor signal circuit and the PCM/ECMharness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 8 Go to Step 14

8 Measure the voltage between the Engine CoolantTemperature (ECT) sensor signal circuit and thePCM/ECM harness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 10 Go to Step 15

9 1. Disconnect the EGR valve.2. Measure the voltage between the EGR Pintle

Position sensor signal circuit and the PCM/ECM harness connector and ground.

Does the voltage measure near the specified value?

0 v Go to Step 11 Go to Step 16

ENGINE CONTROLS 1F – 35

DAEWOO V–121 BL4

Step NoYesValue(s)Action

10 Measure the voltage between the TransmissionFluid Temperature (TFT) sensor signal circuit andthe PCM/ECM harness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 18 Go to Step 17

11 Replace the EGR valve.Is the repair complete?

Go to Step 21

12 Locate and repair short to voltage in the MAP sensorsignal circuit.Is the repair complete?

Go to Step 21

13 Locate and repair short to voltage in the TP sensorsignal circuit.Is the repair complete?

Go to Step 21

14 Locate and repair short to voltage in the IAT sensorsignal circuit.Is the repair complete?

Go to Step 21

15 Locate and repair short to voltage in the ECT sensorsignal circuit.Is the repair complete?

Go to Step 21

16 Locate and repair short to voltage in the EGR PintlePosition sensor circuit.Is the repair complete?

Go to Step 21

17 Locate and repair short to voltage in TFT sensor cir-cuit.Is the repair complete?

Go to Step 21

18 Measure the voltage between the Fuel Tank Pres-sure sensor signal circuit and the PCM/ECM har-ness connector and ground.Does the voltage measure near the specified value?

0 v Go to Step 20 Go to Step 19

19 Locate and repair short to voltage in the Fuel TankPressure sensor signal circuit.Is the repair complete?

Go to Step 21

20 Replace the PCM/ECM.Is the repair complete?

Go to Step 21

21 1. Using the scan tool, clear the DiagnosticTrouble Codes (DTCs).

2. Start the engine and idle at normal operatingtemperature.

3. Operate the vehicle within the conditions forsetting the DTCs as specified in the supportingtext.

Does the scan tool indicate that this diagnostic ranand passed?

Go to Step 22 Go to Step 2

22 Check if any additional DTCs areAre any DTCs displayed that have not been diag-nosed?

Go to applica-ble DTC table

System OK

1F – 36IENGINE CONTROLS

DAEWOO V–121 BL4

ENGINE CONTROLS 1F – 37

DAEWOO V–121 BL4

ENGINE CRANKS BUT WILL NOT RUN

Test Description

The number(s) below refer to step(s) on the diagnostictable.

3. By performing a compression test, it can be deter-mined if the engine has the mechanical ability torun.

9. It is important to check for the presence of sparkfrom all of the ignition wires. If spark is present fromone to three of the ignition coil terminals, the crank-shaft position (CKP) sensor is OK.

19. In checking the powertrain control module

(PCM)/engine control module (ECM) outputs for theelectronic spark timing signal, it recommended touse an oscilloscope to view the varying voltage sig-nals. In measuring these outputs with a voltmeter,intermittent errors may occur that cannot be seenby a voltmeter.

35. This step checks for proper operation of the PCM/ECM’s control of the fuel pump circuit.

59. This step checks for a ground signal being suppliedby the PCM/ECM to operate the fuel injectors. Ifthere is no ground present during the cranking ofthe engine, and the fuel injector wiring is OK, thePCM/ECM is at fault.

Engine Cranks But Will Not RunCAUTION : Use only electrically insulated pliers when handling ignition wires with the engine running to preventan electrical shock.

CAUTION : Do not pinch or restrict nylon fuel lines to avoid damage that could cause a fuel leak, resulting inpossible fire or personal injury.

Important : If engine cranks but will not start, make sure fuel cut–off switch has not been tripped.

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the system check complete?

Go to Step 2 Go to ”On–Board Diagnos-

tic SystemCheck”

2 Crank the engine.Does the engine start and continue to run?

System OK Go to Step 3

3 Perform a cylinder compression test.Is the cylinder compression for all of the cylinders ator above the value specified?

689 kPa (100psi)

Go toStep 7 Go toStep 4

4 Inspect the timing belt alignment.Is the timing belt in alignment?

Go toStep 6 Go toStep 5

5 Align or replace the timing belt as needed.Is the repair complete?

Go toStep 2

6 Repair the internal engine damage as needed.Is the repair complete?

Go toStep 2

7 Inspect the fuel pump fuse.Is the problem found?

Go toStep 8 Go toStep 9

8 Replace the fuse.Is the repair complete?

Go toStep 2

9 Check for the presence of spark from all of the igni-tion wires while cranking the engine.Is spark present from all of the ignition wires?

Go toStep 34 Go toStep 10

10 1. Measure the resistance of the ignition wires.2. Replace any of the ignition wire(s) with a resist-

ance above the value specified.3. Check for the presence of spark from all of the

ignition wires.Is spark present from all of the ignition wires?

30,000 Go toStep 2 Go toStep 11

1F – 38IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

11 1. Turn the ignition OFF.2. Disconnect the Crankshaft Position (CKP) sen-

sor connector.3. Turn the ignition ON.4. Measure the voltage between the CKP connec-

tor terminals 1 and 3.Does the voltage measure near the value specified?

1.08 volts Go toStep 12 Go toStep 13

12 Measure the voltage between the CKP connectorterminals 2 and 3.Does the voltage measure near the value specified?

1.08 volts Go toStep 19 Go toStep 14

13 Measure the voltage between the CKP connectorterminals 1 and ground.Does the voltage measure near the value specified?

1.08 volts Go toStep 15 Go toStep 16

14 Measure the voltage between the CKP connectorterminals 2 and ground.Does the voltage measure near the value specified?

1.08 volts Go toStep 15 Go toStep 17

15 Check for an open or short in the wire between theCKP connector terminal 3 and ground.Is the problem found?

Go toStep 18 Go toStep 33

16 Check for an open or short in the wire between theCKP connector terminal 1 and the powertrain controlmodule (PCM)/engine control module (ECM) con-nector terminal C6.Is the problem found?

Go toStep 18 Go toStep 33

17 Check for an open or short in the wire between theCKP connector terminal 2 and the PCM/ECM con-nector terminal C5.Is the problem found?

Go toStep 18 Go toStep 33

18 Repair the wiring as needed.Is the repair complete?

Go toStep 2

19 1. Disconnect the electronic ignition (EI) systemignition coil connector to prevent the vehiclefrom starting.

2. Measure the voltage at the PCM/ECM connec-tor terminal C6 by backprobing the PCM/ECMconnector.

Are the voltage readings near the values specified?

1.08 v with igni-tion ON, 1.20 vduring cranking

Go toStep 20 Go toStep 21

20 Measure the voltage at the PCM/ECM connectorterminal C5 by backprobing the PCM/ECM connec-tor.Are the voltage readings near the values specified?

1.08 v with igni-tion ON, 1.20 vduring cranking

Go toStep 22 Go toStep 21

21 Replace the CKP sensor.Is the repair complete?

Go toStep 2

22 1. Turn the ignition OFF.2. Disconnect the electrical connector at the EI

system ignition coil.3. Connect a test light between terminal D of the

EI system ignition coil connector and ground.4. Turn the ignition ON.Is the test light on?

Go toStep 23 Go toStep 24

ENGINE CONTROLS 1F – 39

DAEWOO V–121 BL4

Step NoYesValue(s)Action

23 Connect a test light between terminal C of the EI sys-tem ignition coil connector and battery positive.Is the test light on?

Go toStep 27 Go toStep 25

24 Check for an open in the wiring between the batteryand the EI system ignition coil connector terminal D.Is the problem found?

Go toStep 26 Go to”Ignition 1Relay Circuit

Check”

25 Check for an open in the wire from the EI systemignition coil to ground.Is the problem found?

Go toStep 26

26 1. Repair the wiring as needed.2. Connect the EI system ignition coil connector.3. Check for the presence of spark from all of the

ignition wires.Is spark present from all of the ignition wires?

Go toStep 2 Go toStep 27

27 1. Turn the ignition OFF.2. Disconnect the EI system ignition coil connec-

tor.3. While cranking the engine, measure the volt-

age at the EI system ignition coil connectorterminal B.

Does the voltage fluctuate within the values speci-fied?

0.2–2.0 v Go toStep 28 Go toStep 29

28 While cranking the engine, measure the voltage atthe EI system ignition coil connector terminal A.Does the voltage fluctuatewithin the values speci-fied?

0.2–2.0 v Go toStep 32 Go toStep 30

29 Check for an open in the wire from the EI systemignition coil connector terminal B to the PCM/ECMconnector terminal C4.Is the problem found?

Go toStep 31 Go toStep 33

30 Check for an open in the wire from the EI systemignition coil connector terminal A to the PCM/ECMconnector terminal D5.Is the problem found?

Go toStep 31 Go toStep 33

31 1. Repair the wiring as needed.2. Connect the EI system ignition coil connector.3. Check for the presence of spark from all of the

ignition wires.Is spark present from all of the ignition wires?

Go toStep 2 Go toStep 32

32 Replace the EI system ignition coil.Is the repair complete?

Go toStep 2

33 Replace the PCM/ECM.Is the repair complete?

Go toStep 2

34 1. Turn the ignition OFF.2. Connect a fuel pressure gauge.3. Crank the engine.Is any fuel pressure present?

Go toStep 37 Go toStep 35

1F – 40IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

35 1. Turn the ignition OFF.2. Disconnect the electrical connector at the fuel

pump.3. Connect a test light between the fuel pump

connector terminals 3 and 2.4. Turn the ignition ON.5. With the ignition ON, the test light should light

for the time specified.Is the test light on?

2 sec Go toStep 36 Go toStep 46

36 Replace the fuel pump.Is the repair complete?

Go toStep 2

37 Is the fuel pressure within the value specified? 283–324 kPa(41–47 psi)

Go toStep 41 Go toStep 38

38 1. Check the fuel filter for a restriction.2. Inspect the fuel lines for kinks and restrictions.Is the problem found?

Go toStep 39 Go toStep 40

39 1. Replace the fuel filter and/or the fuel lines asneeded.

2. Connect a fuel pressure gauge.3. Crank the engine.Is the fuel pressure within the value specified?

283–324 kPa(41–47 psi)

Go toStep 2 Go toStep 40

40 1. Disconnect the vacuum line from the fuel pres-sure regulator.

2. Inspect the vacuum line for the presence offuel.

3. Inspect the fuel pressure regulator vacuum portfor the presence of fuel.

Is any fuel present?

Go toStep 43 Go toStep 44

41 Check the fuel for contamination.Is the fuel contaminated?

Go toStep 42 Go toStep 58

42 1. Remove the contaminated fuel from the fueltank.

2. Clean the fuel tank as needed.Is the repair complete?

Go toStep 2

43 Replace the fuel pressure regulator.Is the repair complete?

Go toStep 2

44 1. Remove the fuel pump assembly from the fueltank.

2. Inspect the fuel pump sender and the fuel cou-pling hoses for a restriction.

3. Inspect the in–tank fuel filter for a restriction.Is the problem found?

Go toStep 45 Go toStep 36

45 Replace the fuel pump sender, the in–tank fuel filter,and/or the fuel coupling hoses as needed.Is the repair complete?

Go toStep 2

ENGINE CONTROLS 1F – 41

DAEWOO V–121 BL4

Step NoYesValue(s)Action

46 1. Turn the ignition OFF.2. Disconnect the electrical connector at the fuel

pump.3. Connect a test light between the fuel pump

connector terminal 3 and a known goodground.

4. Turn the ignition ON.5. With the ignition ON, the test light should illumi-

nate for the time specified.Is the test light on?

2 sec Go toStep 47 Go toStep 48

47 Repair the open wire between the fuel pump connec-tor terminal 2 and ground.Is the repair complete?

Go toStep 2

48 1. Turn the ignition OFF.2. Disconnect the fuel pump relay.3. Connect a test light between the fuel pump

relay connector terminal 85 and ground.4. Turn the ignition ON.Is the test light on?

Go toStep 49 Go toStep 60

49 1. Turn the ignition OFF.2. Connect a test light between the fuel pump

relay connector terminal 86 and terminal 85.3. Turn the ignition ON.4. With the ignition ON, the test light should light

for the time specified.Is the test light on?

2 sec Go toStep 50 Go toStep 52

50 1. Turn the ignition OFF.2. Connect a test light between the fuel pump

relay connector terminal 30 and ground.Is the test light on?

Go toStep 51 Go toStep 63

51 1. Turn the ignition ON.2. Measure the voltage at the fuse EF19 connec-

tion.Is the voltage within the specified value?

11–14 v Go toStep 53 Go toStep 52

52 Replace the fuel pump relay.Is the repair complete?

Go toStep 2

53 Measure the voltage at the fuse EF19 again.Is the voltage within the specified value?

11–14 v Go toStep 55 Go toStep 54

54 Replace the engine fuse block.Is the repair complete?

Go toStep 2

55 1. Disconnect the fuel cutoff switch connector.2. Measure the voltage at terminal 1 of the fuel

cutoff switch connector.Is the voltage within the specified value?

11–14 v Go toStep 57 Go toStep 56

56 Repair the open or short between the fuel cutoffswitch and fuse EF19.Is the repair complete?

Go toStep 2

57 1. Reconnect the fuel cutoff switch.2. Measure the voltage at terminal 3 of the fuel

cutoff switch connector.Is the voltage within the specified value?

11–14 v Go toStep 58 Go toStep 59

1F – 42IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

58 Repair the short or opening the circuit between thefuel cutoff switch and the fuel pump.Is the repair complete?

Go toStep 2

59 Replace the fuel cutoff switch.Is the repair complete?

Go toStep 2

60 Check the wire between the fuel pump relay connec-tor terminal 85 to the PCM/ECM connector terminalE13 for an open.Is the problem found?

Go toStep 61 Go toStep 33

61 Repair the wire between the fuel pump relay connec-tor terminal 85 to the PCM/ECM connector terminalE13.Is the repair complete?

Go toStep 2

62 Repair the wire between the fuel pump relay connec-tor terminal 30 and the battery.Is the repair complete?

Go toStep 2

63 1. Turn the ignition OFF.2. Disconnect the fuel injector harness connectors

from all of the fuel injectors.3. Turn the ignition ON.4. Connect a test light between the fuel injector

harness connector 1 and ground.5. Repeat Step 4 for each of the remaining fuel

injectors.Is the test light on at all of the fuel injectors?

Go toStep 64 Go toStep 67

64 1. Turn the ignition OFF.2. Connect a test light between the fuel injector

harness connector terminal 2 and battery posi-tive.

3. Crank the engine.4. Repeat Steps 3 and 4 for each of the remain-

ing fuel injectors.Does the test light flash for all of the fuel injectors?

Go toStep 65 Go toStep 68

65 Measure the resistance of each fuel injector.Is the resistance within the value specified (the re-sistance will increase slightly at higher tempera-tures)?

11.6–12.4 System OK Go toStep 66

66 Replace any of the fuel injectors with a resistanceout of specification.Is the repair complete?

Go toStep 2

67 Repair the open wire(s) between the fuel injectorharness connector(s) terminal 1 and the battery.Is the repair complete?

Go toStep 2

68 1. Check for an open between the fuel injectorharness connector terminal 2 and the PCM/ECM connector terminal C4 for the fuel injec-tors one and four.

2. Check for an open between the fuel injectorharness connector terminal 2 and the PCM/ECM connector terminal C6 for the fuel injec-tors two and three.

Is the problem found?

Go toStep 69 Go toStep 71

ENGINE CONTROLS 1F – 43

DAEWOO V–121 BL4

Step NoYesValue(s)Action

69 Repair the open fuel injector harness wire(s).Is the repair complete?

Go toStep 2

70 Replace the fuse or repair the wiring as needed.Is the repair complete?

Go toStep 2

71 1. Inspect the engine fuse block fuse EF34.2. Check for an open in the fuel injector connector

terminals 1 and the ignition 1 relay connectorterminal 87.

Is the problem found?

Go toStep 68 Go to”IgnitionSystem Check”

1F – 44IENGINE CONTROLS

DAEWOO V–121 BL4

NO MALFUNCTION INDICATOR LAMPCircuit DescriptionWhen the ignition is turned ON, the Malfunction IndicatorLamp (MIL) will momentarily flash on and off, then it will re-main on until the engine is running if no Diagnostic TroubleCodes (DTC) are stored. Battery voltage is suppliedthrough the ignition switch directly to the MIL telltale. Thepowertrain control module (PCM)/engine control module(ECM) controls the MIL by providing a ground paththrough the MIL control circuit to turn on the MIL.

Diagnostic AidsAn open ignition #5 fuse will cause the entire cluster to beinoperative, and may set DTC P1625.

Check the battery and ignition feed circuits for poor con-nections if the MIL is intermittent.

Any circuitry, that is suspected as causing an intermittentcomplaint, should be thoroughly checked for backed–outterminals, improper mating, broken locks, improperlyformed or damaged terminals, poor terminals–to–wiringconnections or physical damage to the wiring harness.

Test DescriptionNumber(s) below refer to the step number(s) on the diag-nostic table.

1. The On–Board Diagnostic (OBD II) System Checkprompts the technician to complete some basicchecks and store the freeze frame and failure re-cords data on then scan tool, if applicable. Thiscreates an electronic copy of the data taken whenthe malfunction occurred. The information is storedin the scan tool for later reference.

3. Connections that are suspected of being faultyshould be thoroughly checked as described in thediagnostic aids.

4. If the engine fails to start and the MIL is inopera-tive, then the fault can be isolated to either thePCM/ECM ignition feed, The battery feed, or a poorground at the engine block, or the PCM/ECM.

6. Probing the MIL circuit with a test light to groundstimulates the PCM/ECM’s control of the MIL. If theMIL illuminates, then the malfunction can be iso-lated to the control of the MIL or a poor connectionat the MIL terminal to the PCM/ECM. Connectionsthat are suspected of being faulty should be thor-oughly checked as described in the diagnostic aids.

8. It takes very little resistance for the battery and igni-tion feed circuits to cause an intermittent conditionand should also be checked for a poor connectionas described in diagnostic aids.

ENGINE CONTROLS 1F – 45

DAEWOO V–121 BL4

11. Before replacing the PCM/ECM, check for backed-out terminals, improper mating, broken locks, im-properly formed or damaged terminals, poor termi-nal–to–wiring harness. Replacement PCM/ECM’smust be reprogrammed. Refer to the latest Techlineinformation for reprogramming procedures.

20. PCM/ECM grounds will only cause a problem if allof the grounds are not making a good connection. If

a PCM/ECM ground problem is suspected, themost probable place to check is where all thegrounds meet, at the engine block.

22. If not faults have been found at this point and noDTCs were set, refer to the diagnostic aids for addi-tional checks and information.

No Malfunction Indicator Lamp

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the system check complete?

Go to Step 2 Go to ”On–Board Diagnos-

tic SystemCheck”

2 Turn the ignition switch ON, with the engine OFF.Is the Malfunction Indicator Lamp (MIL) on?

Go to Step 3 Go to Step 4

3 Check for a poor connection at the battery feed ter-minal A4 or ignition feed terminal F16.Is the problem found and repaired?

Go to Step 22 Go to Step 5

4 Attempt to start the engine.Does the engine start?

Go to Step 6 Go to Step 5

5 Check for a faulty powertrain control module(PCM)/engine control module (ECM) ground con-nection at the engine block or PCM/ECM connectorground terminals and repair as necessary.Is the repair complete?

Go to Step 22

6 1. Turn the ignition OFF.2. Disconnect the PCM/ECM connectors from the

PCM/ECM.3. Turn the ignition switch ON.Is the MIL ON?

Go to Step 8 Go to Step 9

7 Inspect the ignition and battery feed fuses.Are the fuses OK?

Go to Step 10 Go to Step 11

8 Check for a poor connection in the battery feed ter-minal A4, ignition feed terminal F16 or the MIL con-trol circuits and repair as necessary.Is a repair necessary?

Go to Step 22 Go to Step 12

9 Probe the MIL control circuit with a test light con-nected to ground.Is the test light illuminated?

Go to Step 13 Go to Step 14

10 1. Turn the ignition switch OFF.2. Disconnect the PCM/ECM connectors from the

PCM/ECM.3. Turn the ignition switch ON.4. Probe the battery feed terminal A4 with a test

light connected to ground.Does the test light illuminate?

Go to Step 15 Go to Step 16

11 1. Check for a short to ground in the circuit of thefuse that was open and repair if necessary.

2. Replace the open fuse.Is the repair complete?

Go to Step 22

1F – 46IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

12 Replace the PCM/ECM.Is the repair complete?

Go to Step 22

13 Repair the short to voltage in the MIL control circuit.Is the repair complete?

Go to Step 22

14 Check for an open or a poor connection in the MILcontrol circuit and repair as necessary.Is the repair necessary?

Go to Step 22 Go to Step 17

15 With a test light still connected to the ground, probethe ignition feed terminal F16.Does the test light illuminate?

Go to Step 18 Go to Step 19

16 Repair the open battery feed circuit.Is the repair complete?

Go to Step 22

17 Check for an open ignition feed circuit or fuse to theMIL and repair as necessary.Is the repair necessary?

Go to Step 22 Go to Step 20

18 Check for a poor connection in the battery feed ter-minal A4 or the ignition feed terminal F16 and repairas necessary.Is the repair necessary?

Go to Step 22 Go to Step 21

19 Repair the open in the ignition feed circuit from termi-nal F16.Is the repair complete?

Go to Step 22

20 Replace the instrument panel cluster. Refer to Sec-tion 9E, Instrumentation/Driver Information.Is the repair complete?

Go to Step 22

21 Check for a faulty PCM/ECM ground connection atthe engine block or PCM/ECM connector and repairas necessary.Is the repair necessary?

Go to Step 22 Go to Step 12

22 1. Allow the engine to idle until normal operatingtemperature is reached.

2. Check if any Diagnostic Trouble Codes (DTCs)are set.

Are any DTCs displayed that have not been diag-nosed?

Go to the appli-cable DTC

table

System OK

ENGINE CONTROLS 1F – 47

DAEWOO V–121 BL4

MALFUNCTION INDICATOR LAMP ON STEADYCircuit DescriptionWhen the ignition is turned ON, the Malfunction IndicatorLamp (MIL) will momentarily flash on and off, then it will re-main on until the engine is running if no Diagnostic TroubleCodes (DTCs) are stored. Battery voltage is suppliedthrough the ignition switch directly to the MIL telltale. Thepowertrain control module (PCM)/engine control module(ECM) controls the MIL by providing a ground paththrough the MIL control circuit to turn on the MIL.

Test DescriptionNumber(s) below refer to the step number(s) on the diag-nostic table.1. The On–Board Diagnostic (OBD II) System Check

prompts the technician to complete some basicchecks and store the freeze frame and failure re-

cords data on then scan tool, if applicable. Thiscreates an electronic copy of the data taken whenthe malfunction occurred. The information is storedin the scan tool for later reference.

2. When the ignition is turned ON, the MIL should mo-mentarily flash on and off, then remain on until theengine is running or if an emission related DTC isstored.

3. This step checks the ability of the PCM/ECM tocontrol the MIL. The scan tool has the ability tocommand the MIL on and off.

5. A shorted MIL circuit can be diagnosed with a scantool.

7. The replacement PCM/ECM must be repro-grammed. Refer to the latest Techline informationfor reprogramming procedures.

1F – 48IENGINE CONTROLS

DAEWOO V–121 BL4

Malfunction Indicator Lamp On Steady

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the system check complete?

Go to Step 2 Go to ”On–Board Diagnos-

tic SystemCheck”

2 Turn the ignition switch ON, with the engine OFF.Is the Malfunction Indicator Lamp (MIL) on?

Go to Step 3 Go to ”No Mal-function Indica-

tor Lamp”

3 1. Install the scan tool.2. Command the MIL on and off.Does the MIL turn on and off when commanded?

Go to Step 8 Go to Step 4

4 1. Turn the ignition switch OFF.2. Disconnect the powertrain control module

(PCM)/engine control module (ECM) connec-tors.

3. Turn the ignition switch ON.Is the MIL off?

Go to Step 7 Go to Step 5

5 Check the MIL control circuit for a short to groundand repair if necessary.Is the repair necessary?

Go to Step 8 Go to Step 6

6 Replace the instrument panel cluster. Refer to Sec-tion 9E, Instrumentation/Driver Information.Is the repair complete?

Go to Step 8

7 Replace the PCM/ECM.Is the repair complete?

Go to Step 8

8 1. Using the scan tool, clear the DiagnosticTrouble Codes (DTCs).

2. Attempt to start the engine.Does the engine start and continue to run?

Go to Step 9 Go to Step 1

9 1. Allow the engine to idle until normal operatingtemperature is reached.

2. Check if any DTCs are set.Are any DTCs displayed that have not been diag-nosed?

Go to the appli-cable DTC

table

System OK

ENGINE CONTROLS 1F – 49

DAEWOO V–121 BL4

FUEL SYSTEM DIAGNOSIS

Circuit Description

The fuel pump is an in–tank fuel pump mounted to a fuelsender assembly. The fuel pump will remain on as long asthe engine is cranking or running and the powertrain con-trol module (PCM)/engine control module (ECM) is receiv-ing reference pulses from the crankshaft position (CKP)sensor. If there are no reference pulses, the PCM/ECMwill turn off the fuel pump 2 seconds after the ignitionswitch is turned ON or 2 seconds after the engine stopsrunning. The fuel pump delivers fuel to the fuel rail and thefuel injectors, where the fuel system pressure is controlledfrom 284 to 325 kPa (41 to 47 psi) by the fuel pressure reg-ulator. The excess fuel is returned to the fuel tank.

Test Description

The number(s) below refer to step(s) on the diagnostictable.

2. When the engine is idling, the intake manifold vacu-um is high. This vacuum is applied to the fuel pres-sure regulator diaphragm, offsetting the springpressure inside the fuel pressure regulator and low-ering the fuel pressure.

10. If there is fuel bleeding back through the fuel returnoutlet, this is due to a faulty fuel pressure regulator.

14. Another symptom often present when the fuel injec-tors are leaking is hard starting. Leaking fuel injec-tors can cause a flooding condition.

23. Fuel leaking from the fuel pump inlet is due to afaulty one–way check valve in the fuel pump.

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.

CAUTION : Do not pinch or restrict nylon fuel lines toavoid damage that could cause a fuel leak, resultingin possible fire or personal injury.

Fuel Pressure Relief Procedure

1. Remove the fuel cap.2. Remove the fuel pump fuse EF18 from the engine

fuse box.3. Start the engine and allow the engine to stall.4. Crank the engine for an additional 10 seconds.

Fuel System Diagnosis

Step Action Value(s) Yes No

1 1. Relieve the fuel system pressure.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified andholding steady?

284–325 kPa(41–47 psi)

Go to Step 2 Go to Step 5

2 1. Disconnect the fuel pressure regulator vacuumhose.

2. Start the engine.3. Allow the engine to idle.4. Connect the fuel pressure regulator vacuum

hose.Does the fuel pressure decrease?

System OK Go to Step 3

3 1. Allow the engine to idle.2. Disconnect the vacuum hose from the fuel

pressure regulator.3. Connect a vacuum pump with a gauge to the

fuel pressure regulator vacuum port.4. Apply 41–47 kPa (12–14 in. Hg) of vacuum to

the fuel pressure regulator.Does the fuel pressure decrease?

Go to Step 4 Go to Step 16

4 1. Locate and correct the cause of the vacuumrestriction to the fuel pressure regulator.

2. Confirm the operation of the fuel pressure reg-ulator.

Is the repair complete?

System OK

1F – 50IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

5 1. Relieve the fuel system pressure.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

Go to Step 6 Go to Step 17

6 Inspect the fuel lines for a leak.Is the problem found?

Go to Step 7 Go to Step 8

7 1. Replace the fuel line(s) as needed.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

System OK

8 1. Remove the fuel pump assembly.2. With the fuel pump under pressure, inspect the

fuel pump coupling hoses for leaking.Is the problem found?

Go to Step 9 Go to Step 10

9 1. Tighten or replace the fuel pump couplinghoses as needed.

2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

System OK

10 With the fuel system under pressure, inspect the fuelreturn outlet for leaking.Is the problem found?

Go to Step 11 Go to Step 12

11 1. Replace the fuel pressure regulator.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

System OK

12 With the fuel system under pressure, inspect the fuelinlet for leaking.Is the problem found?

Go to Step 13 Go to Step 14

13 1. Replace the fuel pump assembly.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

System OK

14 1. Remove the fuel rail and the fuel injectors asan assembly.

2. With the fuel system under pressure, inspectall of the fuel injectors for leaking.

Is the problem found?

Go to Step 15

15 1. Replace the leaking fuel injector(s).2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel pressure within the values specified butnot holding steady?

284–325 kPa(41–47 psi)

System OK

ENGINE CONTROLS 1F – 51

DAEWOO V–121 BL4

Step NoYesValue(s)Action

16 1. Replace the fuel pressure regulator.2. Disconnect the fuel pressure regulator vacuum

hose.3. Start the engine.4. Allow the engine to idle.5. Connect the fuel pressure regulator vacuum

hose.Does the fuel pressure decrease?

System OK

17 1. Relieve the fuel system pressure.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel system pressure below the values speci-fied and holding steady?

284–325 kPa(41–47 psi)

Go to Step 13 Go to Step 18

18 1. Relieve the fuel system pressure.2. Install a fuel pressure gauge.3. Turn the ignition ON.Is the fuel system pressure below the values speci-fied and holding steady?

284–325 kPa(41–47 psi)

Go to Step 19

19 Inspect the fuel lines for leaks.Is the problem found?

Go to Step 7 Go to Step 20

20 1. Remove the fuel pump assembly.2. With the fuel pump under pressure, inspect the

fuel pump coupling hoses for leaking.Is the problem found?

Go to Step 9 Go to Step 21

21 1. Remove the fuel pump assembly.2. With the fuel system under pressure, inspect

the fuel return outlet for leaking.Is the problem found?

Go to Step 11 Go to Step 22

22 1. Remove the fuel pump assembly.2. With the fuel system under pressure, inspect

the fuel inlet for leaking.Is the problem found?

Go to Step 13 Go to Step 23

23 1. Remove the fuel rail and the fuel injectors asan assembly.

2. With the fuel system under pressure, inspectall of the fuel injectors for leaking.

Is the problem found?

Go to Step 15 Go to Step 13

1F – 52IENGINE CONTROLS

DAEWOO V–121 BL4

FUEL PUMP RELAY CIRCUIT CHECK

Circuit Description

When the ignition switch is turned ON, the powertrain con-trol module (PCM)/engine control module (ECM) will acti-vate the fuel pump relay and run the in–tank fuel pump.The fuel pump will operate as long as the engine is crank-ing or running and the PCM/ECM is receiving ignition ref-erence pulses.

If there are no reference pulses, the PCM/ECM will shutoff the fuel pump within 2 seconds after the ignition switchis turned ON.

Diagnostic Aids

An intermittent problem may be caused by a poor connec-

tion, rubbed through wire insulation, or a broken wire in-side the insulation.

Test DescriptionThe number(s) below refer to step(s) on the diagnostictable.

3. This step checks for the PCM/ECM providing aground for the operation of the fuel pump relay.

7. By confirming that the wiring is OK using Steps 2through 6, it can be determined that the fuel pumprelay is at fault.

9. After determining that there is no ground being pro-vided by the PCM/ECM to the fuel pump relay, thefault is either the PCM/ECM or the wiring betweenthe PCM/ECM and the fuel pump relay.

ENGINE CONTROLS 1F – 53

DAEWOO V–121 BL4

Fuel Pump Relay Circuit Check

Step Action Value(s) Yes No

1 1. Turn the ignition OFF for 10 seconds.2. Turn the ignition ON.3. Listen for in–tank fuel pump operation.Does the fuel pump operate for the time specified?

2 sec System OK Go to Step 2

2 1. Turn the ignition OFF.2. Disconnect the fuel pump relay.3. Connect a test light between the fuel pump

relay connector terminal 86 and battery posi-tive.

4. Turn the ignition ON.Is the test light on?

Go to Step 3 Go to Step 8

3 1. Turn the ignition OFF.2. Connect a test light between the fuel pump

relay connector terminal 85 and battery posi-tive.

3. Turn the ignition ON.4. With the ignition ON, the test light should light

for the time specified.Is the test light on?

2 sec Go to Step 4 Go to Step 9

4 1. Turn the ignition OFF.2. Connect a test light between the fuel pump

relay connector terminal 30 and ground.Is the test light on?

Go to Step 5 Go to Step 11

5 Check for an open or short to ground in the wire be-tween the fuel pump relay connector terminal 87 andthe fuel cutoff switch terminal 1.Is the problem found?

Go to Step 6 Go to Step 7

6 1. Repair the wire between the fuel pump relayconnector terminal 87 and the fuel cutoff switchterminal 1.

2. Install the fuel pump relay.3. Turn the ignition OFF for 10 seconds.4. Turn the ignition ON.Does the fuel pump operate for the time specified?

2 sec System OK

7 1. Replace the fuel pump relay.2. Turn the ignition OFF for 10 seconds.3. Turn the ignition ON.Does the fuel pump operate for the time specified?

2 sec System OK

8 Check for an open wire between the fuel pump relayconnector terminal 86 and the ignition 1 relay con-nector terminal 86.Is the problem found?

Go to Step 13 Go to ”Ignition1 Relay Circuit

Check”

9 Check for an open wire between the fuel pump relayconnector terminal 85 to the powertrain control mod-ule (PCM)/engine control module (ECM) connectorterminal E13.Is the problem found?

Go to Step 10 Go to Step 12

1F – 54IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

10 1. Repair the wire between the fuel pump relayconnector terminal 85 to the PCM/ECM con-nector terminal E13.

2. Install the fuel pump relay.3. Turn the ignition OFF for 10 seconds.4. Turn the ignition ON.Does the fuel pump operate for the time specified?

2 sec System OK

11 1. Repair the wire between the fuel pump relayconnector terminal 30 and the battery.

2. Install the fuel pump relay.3. Turn the ignition OFF for 10 seconds.4. Turn the ignition ON.Does the fuel pump operate for the time specified?

2 sec System OK

12 1. Replace the PCM/ECM.2. Turn the ignition OFF for 10 seconds.3. Turn the ignition ON.Does the fuel pump operate for the time specified?

2 sec System OK

13 Repair the wire between the fuel pump relay connec-tor terminal 86 and the ignition 1 relay connector ter-minal 86.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 357

DAEWOO V–121 BL4

SYMPTOM DIAGNOSIS

IMPORTANT PRELIMINARY CHECKSImportant : Several symptom procedures call for a careful visual/physical inspection. Always perform the visual/physicaltest first. Visual inspections may lead to correcting a problem without further checks and can save valuable time.

Step Action Value(s) Yes No

1 Perform an On–Board Diagnostic (OBD II) SystemCheck.Is the check complete?

Go toStep 2 Go to”On–Board Diagnos-

tic SystemCheck”

2 1. Inspect all of the powertrain control module(PCM)/engine control module (ECM) groundconnections.

2. Inspect all of the vacuum hoses for splits,kinks, and proper connections.

3. Check for air leaks at all of the mounting areasof the intake manifold sealing surfaces.

4. Inspect the ignition wires for cracking, hard-ness, proper routing, and carbon tracking.

5. Inspect the wiring for proper connections,pinches, and cuts.

Are all checks complete?

Go to Appropri-ate Symptom

Table

INTERMITTENTSThe problem may or may not illuminate theMalfunction Indicator Lamp (MIL) or store adiagnostic trouble code (DTC).

Important : Do not use the DTC tables for intermittentproblems. A fault must be present in order to locate theproblem. If a fault is intermittent, use of DTC tables mayresult in the replacement of good parts.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Perform a careful inspection of any suspectcircuits.

2. Inspect for poor mating of the connectorhalves, or terminals not fully seated into theconnector body.

3. Inspect for improperly formed or damaged ter-minals.

4. Inspect for poor terminal to wire connections.This requires removing the terminal from theconnector body to inspect it.

Are any problems present?

Go toStep 3 Go toStep 4

3 Repair the electrical connections as needed.Is the repair complete?

System OK

1F – 358IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

4 Road test the vehicle with a voltmeter connected toa suspected circuit or a scan tool connected to theData Link Connector (DLC).Did the voltmeter or the scan tool indicate an abnor-mal voltage or scan reading?

Go toStep 5 Go toStep 6

5 Replace the sensor in the affected circuit, if a Diag-nostic Trouble Code (DTC) was stored for this circuit(except for the DTCs P0171 and P0172.Is the repair complete?

System OK

6 Does an intermittent Malfunction Indicator Lamp(MIL) or DTC occur?

Go toStep 7 Go toStep 8

7 1. Check for a faulty relay, electronic control mod-ule (ECM) driven solenoid, or switch.

2. Check for improper installation of electrical de-vices, such as lights, two–way radios, electricmotors, etc.

3. Inspect the ignition control wires for properrouting (away from ignition wires, ignition sys-tem components, and the generator).

4. Check for a short–to–ground in the MIL circuitor the DLC ”test” terminal.

5. Inspect the PCM/ECM ground connections.6. Correct or repair the affected circuits as need-

ed.Is the repair complete?

System OK

8 1. Check for a loss of DTC memory.2. Disconnect the Throttle Position Sensor.3. Run the engine at idle until the MIL comes on.4. Turn the ignition OFF.Is DTC P0122 stored in memory?

Go toStep 10 Go toStep 9

9 Replace the PCM/ECM.Is the repair complete?

System OK

10 Does the vehicle stall while driving? Go toStep 11 Go toStep 12

11 Monitor the oxygen sensor (O2S) and the injectorbase pulse width with the scan tool.Does the scan tool display a steady low voltage(about 0 mv) for the O2S sensor with the controlmodule commanding an injector base pulse width ofthe value specified?

8 ms Go toStep 9 Go toStep 12

12 1. Check for an open diode across the A/C clutchand for other open diodes.

2. Repair or replace any components as needed.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 359

DAEWOO V–121 BL4

HARD STARTThe engine cranks OK, but does not start for a longtime. The engine eventually runs or may start andimmediately die.

Important : Ensure that the driver is using the correctstarting procedure. Before diagnosing, check service bul-letins for updates.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Connect the scan tool to the Data Link Con-nector (DLC).

2. Check the Engine Coolant Temperature (ECT)sensor and the Intake Air Temperature (IAT)sensor using the scan tool.

3. Compare the coolant temperature and the IATwith the ambient temperature when the engineis cold.

Do the ECT and the IAT readings differ from the am-bient temperature by more than the value specified?

5³F (3³C) Go toStep 3 Go toStep 4

3 1. Measure the resistance of the ECT and the IATsensor.

2. Compare the resistance value to specificationsusing the Temperature Vs. Resistance tablesfor diagnostic trouble codes (DTCs) P0118 andP0113.

3. If the resistance is not the same, replace thefaulty sensor.

Is the repair complete?

System OK

4 1. Check for a sticking throttle shaft or a bindinglinkage that may cause a high Throttle Position(TP) sensor voltage. Repair or replace asneeded.

2. Check the TP sensor voltage reading with thethrottle closed.

Does the voltage measure within the value speci-fied?

0.4–0.8 v Go toStep 5 Go toStep 26

5 1. Check the Manifold Absolute Pressure (MAP)sensor response and accuracy.

2. Replace the MAP sensor as needed.Is the repair complete?

System OK Go toStep 6

6 Check the fuel pump operation.Does the fuel pump operate for the specified timewhen the ignition switch is turned ON?

2 sec Go toStep 7 Go to”FuelPump Relay

Circuit Check”

7 Check the fuel system pressure.Is the fuel pressure within the specifications?

(284–325 kPa)41–47 psi

Go toStep 29 Go toStep 8

8 Check for water contamination in the fuel.Is fuel contaminated?

Go toStep 9 Go toStep 10

9 Replace the contaminated fuel.Is the repair complete?

System OK

1F – 360IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

10 1. Check the fuel injector driver circuit.2. Disconnect all of the fuel injector harness con-

nectors at the fuel injectors.3. Connect an injector test light between the har-

ness terminals of each fuel injector connector.4. Note the test light while cranking the engine.Does the test light blink at all connectors?

Go toStep 13 Go toStep 11

11 Check the fuel injector driver wiring harness, theconnectors, and the connector terminals for theproper connections.Is the problem found?

Go toStep 12 Go toStep 30

12 Repair the wiring harness, the connector, or the con-nector terminal as needed.Is the repair complete?

System OK

13 Measure the resistance of each fuel injector at 68³F(20³C). The resistance will increase slightly at high-er temperatures.Is the fuel injector resistance within the value speci-fied?

11.6–12.4 Ω Go toStep 15 Go toStep 14

14 Replace any fuel injector with a resistance that is outof specifications.Is the repair complete?

System OK

15 Perform an injector balance test.Is the problem found?

Go toStep 16 Go toStep 17

16 Replace any restricted or leaking fuel injectors asneeded.Is the repair complete?

System OK

17 1. Check for the proper ignition voltage output foreach cylinder with a spark tester.

2. Inspect the spark plugs for cracks, wear, im-proper gap, burned electrodes, or heavy de-posits.

3. Inspect the ignition wires for short conditions.4. Inspect all of the ignition grounds for loose con-

nections.5. Inspect the powertrain control module

(PCM)/engine control module (ECM) for theproper operation.

Is the problem found?

Go toStep 18 Go toStep 19

18 Correct or replace any faulty ignition components.Is the repair complete?

System OK

19 Does the engine misfire or cut out under load or atidle?

Go to”IgnitionSystem Check”

Go toStep 20

20 Does the engine start, but then immediately stall? Go toStep 21 Go toStep 23

21 1. Remove the Crankshaft Position (CKP) sensor.2. Inspect for faulty connections and repair as

needed.Is the problem found?

Go toStep 22 Go toStep 25

22 Repair the faulty connections as needed.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 361

DAEWOO V–121 BL4

Step NoYesValue(s)Action

23 1. Check for the proper valve timing.2. Check the cylinder compression.3. Inspect the pushrods, the rocker arms, the

valve springs, and the camshaft lobes for ex-cessive wear.

4. Inspect the intake manifold and the exhaustmanifold passages for casting flash.

Is the problem found?

Go toStep 24 Go toStep 25

24 Repair or replace any components as needed.Is the repair complete?

System OK

25 Check the Idle Air Control (IAC) valve operation. Re-pair or replace components as needed.Is the repair complete?

System OK

26 Check the base idle setting of the throttle body.Is the repair complete?

Go toStep 27 Go toStep 28

27 Check the Throttle Position (TP) sensor circuit forproper operation. Repair or replace components asneeded.Is the repair complete?

System OK

28 Adjust the base idle setting to specifications.Is the repair complete?

System OK

29 Repair the fuel system as needed.Is the repair complete?

System OK

30 Replace the PCM/ECM.Is the repair complete?

System OK

SURGES OR CHUGGLESEngine power varies under steady throttle or cruise,making it feel as if the vehicle speeds up and slowsdown with no change in the accelerator pedalposition.

Important : Make sure the driver understands TorqueConverter Clutch (TCC) and A/C compressor operation asdescribed in the owner’s manual

The speedometer reading and the speed reading on thescan tool should be equal.

Before diagnosing the symptom, check service bulletinsfor updates.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 Connect the scan tool to the Data Link Connector(DLC).Does the Oxygen Sensor (O2S) respond quickly todifferent throttle positions?

Go toStep 4 Go toStep 3

3 1. Check the O2S sensor for silicone or othercontaminants from fuel or use of improperRoom Temperature Vulcanizing (RTV) sealant.

2. Replace the contaminated O2S sensor.Is the repair complete?

System OK

1F – 362IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

4 1. Drive the vehicle at the speed of the complaint.2. Monitor the long term fuel trim reading using

the scan tool.Is the long term fuel trim reading within the valuespecified?

115–150counts

Go toStep 7 Go toStep 5

5 Is the long term fuel trim reading below the valuespecified?

115 counts Go to”Diagnos-tic Aids for

DTC P0172”

Go toStep 6

6 Is the long term fuel trim reading above the valuespecified?

150 counts Go to”Diagnos-tic Aids for

DTC P0171”

7 Check the fuel system pressure while the conditionexists.Is the fuel system pressure within specifications?

41–47 psi(284–325 kPa)

Go toStep 8 Go toStep 17

8 Check the in–line fuel filter.Is the filter dirty or plugged?

Go toStep 18 Go toStep 9

9 Perform an injector diagnosis.Does the injector balance test pinpoint the problem?

Go toStep 19 Go toStep 10

10 1. Check for proper ignition voltage output using aspark tester.

2. Inspect the spark plugs for cracks, wear, im-proper gap, burned electrodes, or heavy de-posits.

Is the problem found?

Go toStep 11 Go toStep 12

11 Repair or replace any ignition system componentsas needed.Is the repair complete?

System OK

12 1. Inspect the powertrain control module(PCM)/engine control module (ECM) groundsto make sure they are clean, tight, and in theirproper locations.

2. Inspect the vacuum lines for kinks or leaks.Is the problem found?

Go toStep 13 Go toStep 14

13 Repair the electrical connections or the vacuumlines as needed.Is the repair complete?

System OK

14 Check the generator output voltage.Is the generator voltage within the value specified?

12–16 v Go toStep 16 Go toStep 15

15 Repair the generator.Is the repair complete?

System OK

16 1. Check for intermittent Exhaust Gas Recircula-tion (EGR) valve operation.

2. Check Torque Converter Clutch (TCC) opera-tion.

3. Repair or replace any components as needed.Is the repair complete?

System OK

17 Repair the fuel system as needed.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 363

DAEWOO V–121 BL4

Step NoYesValue(s)Action

18 Replace the fuel filter.Is the repair complete?

System OK

19 Replace the leaking or restricted fuel injectors.Is the repair complete?

System OK

1F – 364IENGINE CONTROLS

DAEWOO V–121 BL4

LACK OF POWER, SLUGGISHNESS, OR SPONGINESSThe engine delivers less than expected power. Thereis little or no increase in speed when the acceleratorpedal is partially applied.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Verify the customer’s complaint.2. Compare the performance of the customer’s

vehicle with a similar unit.Does the problem exist?

Go toStep 3 System OK

3 1. Inspect the air filter for excessive contamina-tion.

2. Replace the air filter as needed.3. Check the transaxle shift pattern and downshift

operation.Does the transaxle operate properly?

Go toStep 4 Go toStep 5

4 Check the fuel system pressure.Is the fuel system pressure within specifications?

41–47 psi(284–325 kPa)

Go toStep 7 Go toStep 6

5 Repair the transaxle as needed.Is the repair complete?

System OK

6 Repair the fuel system as needed.Is the repair complete?

System OK

7 Check for a restricted fuel filter or contaminated fuel.Is the problem found?

Go toStep 8 Go toStep 9

8 Repair or replace any components as needed.Is the repair complete?

System OK

9 1. Check the ignition system output for all of thecylinders using a spark tester.

2. Check for proper ignition control operation.Is the ignition system operating properly?

Go toStep 10 Go toStep 11

10 1. With the engine at normal operating tempera-ture, connect a vacuum gauge to a vacuumport on the intake manifold.

2. Operate the engine at 1,000 rpm.3. Record the vacuum reading.4. Increase the engine speed to 2,500 rpm.5. Note the vacuum reading at a steady 2,500

rpm.Does the vacuum decrease more than the valuespecified?

10 kPa(3 in. Hg)

Go toStep 12 Go toStep 15

11 Repair or replace any ignition system componentsas needed.Is the repair complete?

System OK

12 Inspect the exhaust system for restrictions and dam-aged or collapsed pipes.Is the problem found?

Go toStep 13 Go toStep 14

13 Repair or replace any components as needed.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 365

DAEWOO V–121 BL4

Step NoYesValue(s)Action

14 1. Check the cylinder compression and valve tim-ing.

2. Inspect the camshaft for excessive wear.Is the problem found?

Go toStep 15 Go toStep 16

15 Repair or replace any engine components as need-ed.Is the repair complete?

System OK

16 1. Check the powertrain control module(PCM)/engine control module (ECM) groundsfor being clean, tight, and in their proper loca-tion.

2. Check the Exhaust Gas Recirculation (EGR)valve for being open or partially open all thetime.

3. Check the Torque Converter Clutch (TCC) op-eration.

4. Check the A/C system operation.5. Check the generator output.6. Repair the generator if the output is not within

the specified range.Are all checks and repairs complete?

12–16 v System OK

DETONATION/SPARK KNOCK

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Fill the fuel tank with a known good grade ofgasoline that has the octane rating of the valuespecified.

2. Reevaluate the vehicle’s performance.Does the detonation problem still exist?

87–89 octane Go toStep 3 System OK

3 1. Inspect for low engine coolant.2. Check for restricted airflow to the radiator or

restricted coolant flow.3. Check for a faulty thermostat.4. Check for an incorrect coolant solution.Is the problem found?

Go toStep 4 Go toStep 5

4 Repair or replace any cooling system componentsas needed.Is the repair complete?

System OK

5 1. Check the voltage using the scan tool.2. Replace the Engine Coolant Temperature

(ECT) sensor if the resistance is not withinspecifications as listed in the Diagnostic Aidsfor diagnostic trouble code (DTC) P0118.

Is the problem found?

Go toStep 6 Go toStep 7

6 Replace the ECT sensor or repair the circuit asneeded.Is the repair complete?

System OK

1F – 366IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

7 1. Check the ignition system output with a sparktester.

2. Inspect the spark plugs for the proper heatrange and gap.

3. Check for the proper operation of the ignitioncontrols.

Is the ignition system operating properly?

Go toStep 9 Go toStep 8

8 Repair or replace the ignition system components asneeded.Is the repair complete?

System OK

9 1. Connect the scan tool to the Data Link Con-nector (DLC).

2. Road test the vehicle at the speed of the com-plaint.

3. Monitor the long term fuel trim reading from thescanner data stream.

Is the long term fuel trim reading above the valuespecified?

150 counts Go to”Diagnos-tic Aids for

DTC P0171”

Go toStep 10

10 Check the fuel system pressure.Is the problem found?

41–47 psi(284–325 kPa)

Go toStep 11 Go toStep 12

11 Repair or replace the fuel system components asneeded.Is the repair complete?

System OK

12 1. Inspect for carbon buildup inside the engine.2. Remove the carbon with a top engine cleaner.

Follow the instructions supplied with the prod-uct.

3. Check the basic engine parts such as the cam-shaft, the cylinder head, the pistons, etc. forexcessive wear.

4. Replace any excessively worn parts.Is the procedure complete?

Go toStep 13

13 1. Check the Exhaust Gas Recirculation (EGR)valve for proper operation.

2. Check the air intake system for proper opera-tion.

3. Check the Torque Converter Clutch (TCC) op-eration and transaxle shift points.

4. Check the service bulletins for ProgrammableRead–Only Memory (PROM) updates.

5. Check the cylinder compression.6. Repair or replace any faulty components.Are all checks and repairs complete?

System OK

ENGINE CONTROLS 1F – 367

DAEWOO V–121 BL4

HESITATION, SAG, STUMBLEInvolves a momentary lack of response as theaccelerator is pushed down. This can occur at anyvehicle speed. It is usually the most severe when firsttrying to make the vehicle move, as from a stop.Hesitation, sag, or stumble may cause the engine to

stall if severe enough.

Important : Before diagnosing this condition, check ser-vice bulletins for Programmable Read–Only Memory(PROM) updates.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Check the fuel system pressure. If the pres-sure is not within the value specified, servicethe fuel system as needed.

2. Inspect the Throttle Position (TP) sensor forbinding or sticking. The TP sensor voltageshould increase at a steady rate as the throttleis moved toward Wide Open Throttle (WOT).

Is the problem found?

41–47 psi(284–325 kPa)

Go toStep 3 Go toStep 4

3 Repair or replace any components as needed.Is the repair complete?

System OK

4 1. Check the Manifold Absolute Pressure (MAP)sensor response and accuracy.

2. Inspect the fuel for water contamination.3. Check the Evaporative (EVAP) Emission canis-

ter purge system for proper operation.Is the problem found?

Go toStep 5 Go toStep 6

5 Repair or replace any components as needed.Is the repair complete?

System OK

6 1. Disconnect all of the fuel injector harness con-nectors.

2. Connect an injector test light between the har-ness terminals of each fuel injector.

3. Note the test light while cranking the engine.Does the test light blink on all connectors?

Go toStep 8 Go toStep 7

7 1. Repair or replace the faulty fuel injector driveharness, the connector, or the connector termi-nal.

2. If the connections and the harnesses are good,replace the powertrain control modulePCM)/engine control module (ECM) for an in-ternal open in the fuel injector driver circuit.

Is the repair complete?

System OK

8 Measure the resistance of each fuel injector. The re-sistance will increase slightly at higher tempera-tures.Is the fuel injector resistance within the value speci-fied?

11.6–12.4 Ω Go toStep 10 Go toStep 9

9 Replace any of the fuel injectors with a resistancethat is out of specifications.Is the repair complete?

System OK

10 Perform an injector balance test.Is the problem found?

Go toStep 11 Go toStep 12

1F – 368IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

11 Replace any restricted or leaking fuel injectors.Is the repair complete?

System OK

12 Check the fuel system pressure after a cold start orduring moderate or full throttle acceleration.Is the fuel pressure within specifications?

41–47 psi(284–325 kPa)

Go toStep 14 Go toStep 13

13 Repair the restriction in the fuel system or replacethe faulty fuel pump.Is the repair complete?

System OK

14 1. Check for faulty ignition wires.2. Inspect for fouled spark plugs.3. Check the ignition system output on each cylin-

der with a spark tester.Is the problem found?

Go toStep 15 Go toStep 16

15 Repair or replace any ignition components as need-ed.Is the repair complete?

System OK

16 1. Check the generator output voltage.2. Repair or replace the generator if the generator

output is less than the value specified.3. Check the Exhaust Gas Recirculation (EGR)

valve operation.Are all checks and needed repairs complete?

12–16 v System OK

CUTS OUT, MISSESThis Involves a steady pulsation or jerking thatfollows engine speed, usually more pronounced asengine load increases. The exhaust has a steadyspitting sound at idle or low speed.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 Check the ignition system output voltage for all of thecylinders using a spark tester.Is spark present on all of the cylinders?

Go toStep 3 Go to”IgnitionSystem Check”

3 1. Inspect the spark plugs for excessive wear,insulation cracks, improper gap, or heavy de-posits.

2. Check the resistance of the ignition wires. Re-place any ignition wires that have a resistancegreater than the value specified.

Is the problem found?

30,000 Ω Go toStep 4 Go toStep 5

4 Repair or replace any components as needed.Is the repair complete?

System OK

5 With the engine running, spray the ignition wires witha fine water mist to check for arcing and shorting toground.Is the problem found?

Go toStep 6 Go toStep 7

6 Replace the ignition wires.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 369

DAEWOO V–121 BL4

Step NoYesValue(s)Action

7 1. Perform a cylinder compression test.2. If the compression is low, repair the engine as

needed.3. Inspect for proper valve timing, bent pushrods,

worn rocker arms, broken or weak valvesprings, and worn camshaft lobes.

4. Inspect the intake manifold and the exhaustmanifold passages for casting flash.

Is the problem found?

Go toStep 8 Go toStep 9

8 Repair or replace any components as needed.Is the repair complete?

System OK

9 1. Check the fuel system for a plugged in–line fuelfilter.

2. Check the fuel system for low fuel pressure. Ifthe fuel pressure is below the value specified,service the fuel system as needed.

3. Inspect for contaminated fuel.Is the problem found?

41–47 psi(284–325 kPa)

Go toStep 10 Go toStep 11

10 Repair or replace any components as needed.Is the repair complete?

System OK

11 1. Disconnect all of the fuel injector harness con-nectors at the fuel injectors.

2. Connect an injector test light to the harnessterminals of each fuel injector connector.

3. Note the test light while cranking the engine foreach fuel injector.

Does the test light blink for all of the fuel injectors?

Go toStep 13 Go toStep 12

12 1. Repair or replace the faulty injector drive circuitharness, the connector, or the connector termi-nal.

2. If the harness, the connectors, and the termi-nals are OK, replace the powertrain controlmodule (PCM)/engine control module (ECM).

Is the repair complete?

System OK

13 Measure the resistance of each fuel injector. The re-sistance will increase slightly at higher tempera-tures.Is the injector resistance within the value specified?

11.6–12.4 Ω Go toStep 15 Go toStep 14

14 Replace any fuel injectors with a resistance that isout of specifications.Is the repair complete?

System OK

15 Perform an injector balance test.Is the problem found?

Go toStep 16 Go toStep 17

16 Replace any restricted or leaking fuel injectors.Is the repair complete?

System OK

1F – 370IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

17 1. Check for electromagnetic interference.2. Monitor the engine rpm with a scan tool.Does the scan tool rpm change greatly with littlechange in actual engine rpm?

Go toStep 18

18 1. Inspect the routing of the ignition wires.2. Inspect all of the ignition system grounds.3. Correct the routing or repair the ground con-

nections as needed.Are all checks and needed repairs complete?

System OK

POOR FUEL ECONOMYFuel economy, as measured by an actual road test, isnoticeably lower than expected. Also, fuel economyis noticeably lower than it was on this vehicle at onetime, as previously shown by an actual road test.

Important : Driving habits affect fuel economy. Check theowner’s driving habits by asking the following questions:

1. Is the A/C system (i.e. defroster mode) turned onall the time?

2. Are the tires at the correct air pressure?3. Have excessively heavy loads been carried?4. Does the driver accelerate too much and too often?

Suggest the driver read the section in the owner’smanual about fuel economy.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Inspect the air filter for excessive contamina-tion.

2. Inspect for fuel system leaks.Are all needed checks complete?

Go toStep 3

3 1. Inspect the spark plugs for excessive wear,insulation cracks, improper gap, or heavy de-posits.

2. Replace any faulty spark plugs.3. Inspect the ignition wires for cracking, hard-

ness, and proper connections.Are all needed checks and repairs complete?

Go toStep 4

4 1. Inspect the engine coolant level.2. Check the thermostat for being always open or

for an incorrect heat range.3. Replace the thermostat as needed.Are all needed checks and repairs complete?

Go toStep 5

5 1. Check the transaxle shift pattern. Ensure alltransaxle gears are functioning.

2. Check the Torque Converter Clutch (TCC) op-eration with a scan tool. The scan tool shouldindicate rpm drop when the TCC is command-ed on.

3. Check for proper calibration of the speedome-ter.

4. Check the brakes for dragging.5. Check the cylinder compression.6. Repair, replace, or adjust any components as

needed.Are all checks and needed repairs complete?

System OK

ENGINE CONTROLS 1F – 371

DAEWOO V–121 BL4

ROUGH, UNSTABLE, OR INCORRECT IDLE, STALLINGThe engine runs unevenly at idle. If the condition isbad enough, the vehicle may shake. Also, the idlevaries in rpm (called ”hunting”). Either condition maybe severe enough to cause stalling. The engine idlesat incorrect idle speed.

Important : Before diagnosing the symptom, check ser-vice bulletins for updates.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Connect the scan tool to the Data Link Con-nector (DLC).

2. Monitor the Oxygen Sensor (O2S) reading atdifferent throttle positions.

Does the O2S sensor change quickly from rich tolean at the different throttle positions?

Go toStep 5 Go toStep 3

3 Check the O2S sensor for contamination from fuelor improper use of Room Temperature Vulcanizing(RTV) sealant.Is the O2S sensor contaminated?

Go toStep 4 Go toStep 5

4 Replace the contaminated O2S sensor as needed.Is the repair complete?

System OK

5 1. Check for a sticking throttle shaft or bindingthrottle linkage that may cause incorrectThrottle Position (TP) sensor voltage.

2. Check the TP sensor voltage reading with thethrottle closed.

Is the TP sensor voltage within the value specified?

0.4–0.8 v Go toStep 6 Go to”Diagnos-tic Aids for

DTC P0123”

6 1. Check the Engine Coolant Temperature (ECT)sensor voltage reading using the scan tool.

2. Compare the ECT reading with the ambienttemperature when the engine is cold.

Does the ECT temperature reading differ from theambient temperature by more than the value speci-fied?

5³F (3³C) Go toStep 7 Go toStep 9

7 Check for high resistance in the ECT sensor circuitor the sensor itself.Is the problem found?

Go toStep 8 Go toStep 9

8 Replace the ECT sensor or repair the circuit asneeded.Is the repair complete?

System OK

9 Check the Manifold Absolute Pressure (MAP) sen-sor for response and accuracy.Is the problem found?

Go toStep 10 Go toStep 11

10 Replace the MAP sensor or repair the MAP sensorcircuit as needed.Is the repair complete?

System OK

1F – 372IENGINE CONTROLS

DAEWOO V–121 BL4

Step NoYesValue(s)Action

11 1. Road test the vehicle at the speed of the com-plaint.

2. Monitor the fuel trim reading using the scantool.

Is the fuel trim reading within the value specified?

115–150counts

Go toStep 14 Go toStep 12

12 Is the fuel trim reading below the value specified? 115 counts Go to”Diagnos-tic Aids for

DTC P0172”

Go toStep 13

13 Is the fuel trim reading above the value specified? 150 counts Go to”Diagnos-tic Aids for

DTC P0171”

14 1. Disconnect all of the fuel injector harness con-nectors at the fuel injectors.

2. Connect an injector test light between the har-ness terminals of each fuel injector connector.

3. Note the test light while cranking the engine.Does the test light blink for all of the fuel injectors?

Go toStep 16 Go toStep 15

15 1. Repair or replace the faulty injector drive circuitharness, the connector, or the connector termi-nals as needed.

2. If the harness, the connectors, and the termi-nals are OK, replace the powertrain controlmodule (PCM)/engine control module (ECM).

Is the repair complete?

System OK

16 Measure the resistance of each of the fuel injectors.The resistance will increase slightly at higher tem-peratures.Is the resistance within the value specified?

11.6–12.4 Ω Go toStep 18 Go toStep 17

17 Replace any fuel injectors with a resistance that isout of specifications.Is the repair complete?

System OK

18 Perform an injector balance test.Is the problem found?

Go toStep 19 Go toStep 20

19 Replace any leaking or restricted fuel injectors.Is the repair complete?

System OK

20 1. With the engine OFF, disconnect the fuel pres-sure regulator vacuum hose.

2. Thoroughly inspect the fuel pressure regulatorvacuum port and the fuel pressure regulatorvacuum hose for the presence of fuel.

Is the problem found?

Go toStep 21 Go toStep 22

21 Replace the fuel pressure regulator as needed.Is the repair complete?

System OK

ENGINE CONTROLS 1F – 373

DAEWOO V–121 BL4

Step NoYesValue(s)Action

22 1. Check the ignition system output voltage for allof the cylinders using a spark tester.

2. Inspect the spark plugs for excessive wear,insulation cracks, improper gap, or heavy de-posits.

3. Inspect the ignitionwires for cracking, hard-ness, or improper connections.

4. Replace any ignition wires with a resistanceover the value specified.

Is the problem found?

30,000 Ω Go toStep 23 Go toStep 24

23 Repair or replace any ignition system componentsas needed.Is the repair complete?

System OK

24 1. Inspect for vacuum leaks.2. Check for proper Positive Crankcase Ventila-

tion (PCV) operation.3. Check the Idle Air Control (IAC) valve opera-

tion.4. Inspect the PCM/ECM ground connections.Is the problem found?

Go toStep 25 Go toStep 26

25 Repair or replace any components as needed.Is the repair complete?

System OK

26 1. Check the Exhaust Gas Recirculation (EGR)valve for proper operation.

2. Inspect the battery cables and the groundstraps for proper connections.

3. Check the generator voltage output. Repair orreplace the generator if the voltage output isnot within the value specified.

Is the problem found?

12–16 v Go toStep 27 Go toStep 28

27 Repair or replace any components as needed.Is the repair complete?

System OK

29 1. Inspect for broken engine mounts.2. Check for proper valve timing.3. Perform a cylinder compression test.4. Inspect for bent pushrods, worn rocker arms,

broken or weak valve springs, and a worn cam-shaft.

5. Perform repairs as needed.Are all of the checks and needed repairs complete?

System OK

1F – 374IENGINE CONTROLS

DAEWOO V–121 BL4

EXCESSIVE EXHAUST EMISSIONS OR ODORSA vehicle fails an emission test. The vehicle has an excessive rotten egg smell.

Important : Excessive odors do not necessarily indicate excessive emissions.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Run the engine until it reaches operating tem-perature.

2. Perform an emission test.Does the vehicle pass the emission test?

System OK Go toStep 3

3 1. Connect the scan tool to the Data Link Con-nector (DLC).

2. Road test the vehicle.3. Monitor the long term fuel trim memory.Is the long term fuel trim memory within the valuespecified?

115–150counts

Go toStep 6 Go toStep 4

4 Is the long term fuel trim memory below the valuespecified?

115 counts Go to”Diagnos-tic Aids for

DTC P0172”

Go toStep 5

5 Is the long term fuel trim memory above the valuespecified?

150 counts Go to”Diagnos-tic Aids for

DTC P0171”

6 1. Check for a properly installed fuel cap.2. Check the fuel system pressure.3. Perform an injector balance test.Is the problem found?

Go toStep 7 Go toStep 8

7 1. Repair or replace any fuel system componentsas needed.

2. Perform an emission test.Does the vehicle pass the emission test?

System OK

8 1. Check the ignition system for proper operation.2. Inspect the spark plugs for excessive wear,

insulation cracks, improper gap, or heavy de-posits.

3. Check the ignition wires for cracking, hardness,or improper connections.

Is the problem found?

Go toStep 9 Go toStep 10

ENGINE CONTROLS 1F – 375

DAEWOO V–121 BL4

Step NoYesValue(s)Action

9 1. Repair or replace any ignition system compo-nents as needed.

2. Perform an emission test.Does the vehicle pass the emission test?

System OK

10 1. Inspect for vacuum leaks.2. Inspect the catalytic converter for contamina-

tion.3. Inspect for carbon buildup on the throttle body

and the throttle plate and inside the engine.Remove with a top engine cleaner.

4. Check the Exhaust Gas Recirculation (EGR)valve to make sure it opens.

5. Check for proper Positive Crankcase Ventila-tion (PCV) operation.

Are all checks and needed repairs complete?

System OK

DIESELING, RUN–ONAn engine continues to run after the ignition switchis turned OFF.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 Does the engine run smoothly after the ignitionswitch is turned OFF?

Go toStep 3 Go toStep 4

3 1. Check the ignition switch and the ignitionswitch adjustment.

2. Replace the ignition switch if needed.Is the repair complete?

System OK

4 1. Check the evaporative emission system.2. Check for leaking fuel injectors.3. Check the Idle Air Control (IAC) valve opera-

tion.4. Inspect for vacuum leaks.5. Check for the proper base idle setting.Are all checks and repairs complete?

System OK

1F – 376IENGINE CONTROLS

DAEWOO V–121 BL4

BACKFIREFuel ignites in the intake manifold, or in the exhaustsystem, making a loud popping noise.

Important : Before diagnosing the symptom, check ser-vice bulletins for updates.

Step Action Value(s) Yes No

1 Were the Important Preliminary Checks performed? Go toStep 2 Go to”Impor-tant Preliminary

Checks”

2 1. Inspect for crossed or crossfiring ignition wires.2. Check the ignition system output voltage for all

cylinders using a spark tester.3. Inspect the spark plugs for excessive wear,

burned electrodes, improper gap, or heavy de-posits..

Is the problem found?

Go toStep 3 Go toStep 4

3 Repair or replace any ignition system componentsas needed.Is the repair complete?

System OK

4 1. Check the fuel system operation.2. Check the fuel injectors by performing an injec-

tor diagnosis.Is the problem found?

Go toStep 5 Go toStep 6

5 Repair or replace any fuel system components asneeded.Is the repair complete?

System OK

6 1. Inspect the Exhaust Gas Recirculation (EGR)gasket for a leak or a loose fit.

2. Check the EGR valve for proper operation.3. Inspect the intake manifold and the exhaust

manifold for a casting flash.Is the problem found?

Go toStep 7 Go toStep 8

7 Repair or replace any components as needed.Is the repair complete?

System OK

8 1. Inspect the timing belt for proper installationand tension.

2. Check the engine compression.3. Inspect the intake manifold gasket and the ex-

haust manifold gasket for leaks.4. Check for sticking or leaking valves.5. Repair or replace any components as needed.Are all checks and corrections complete?

System OK

ENGINE CONTROLS 1F – 377

DAEWOO V–121 BL4

MAINTENANCE AND REPAIR

ON–VEHICLE SERVICE

FUEL TANK

Removal Procedure

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.1. Relieve the fuel pressure. Refer to ” Fuel System

Pressure Relief ” in this section.2. Disconnect the negative battery cable.3. Drain the fuel tank.4. Disconnect the right rear parking brake cable from

the retaining bracket attached to the right side fueltank strap.

5. Remove the fuel tank filler tube clamp at the fueltank.

6. Disconnect the fuel tank filler tube.7. Disconnect the fuel tank vent tube at the fuel tank.8. Disconnect the fuel vapor line near the fuel tank

filler tube.

9. Disconnect the fuel pump harness connector nearthe left rear corner of the fuel tank.

10. Disconnect the fuel inlet line and the fuel return linenear the right front of the fuel tank.

11. Disconnect the wiring harness clips and the fuel lineclips as needed.

1F – 378IENGINE CONTROLS

DAEWOO V–121 BL4

12. Support the fuel tank.13. Remove the fuel tank strap retaining nuts.14. Remove the fuel tank straps.15. Carefully lower the fuel tank.16. Remove the fuel tank.17. Transfer any parts as needed.

Installation Procedure

1. Raise the fuel tank into position.2. Install the fuel tank straps.3. Install the fuel tank strap retaining nuts.

TightenTighten the fuel tank strap retaining nuts to 13 Nm(115 lb–ft).

4. Connect the fuel outlet line and the fuel return line.5. Connect the wiring harness clips and the fuel line

clips as needed.6. Connect the fuel pump harness connector.7. Connect the fuel vapor line.8. Connect the fuel tank filler tube.9. Connect the fuel tank vent tube.10. Install the fuel tank filler tube clamp at the fuel tank.

11. Connect the right rear parking brake cable to theretaining bracket attached to the right side fuel tankstrap.

12. Connect the negative battery cable.13. Fill the fuel tank.14. Perform a leak check of the fuel tank and the fuel

line connections.

ENGINE CONTROLS 1F – 379

DAEWOO V–121 BL4

FUEL PUMP

Removal Procedure

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.

1. Relieve the fuel system pressure.

1) Remove the fuel cap.2) Remove fuel pump fuse EF18 from the engine

fuse block.3) Start the engine and allow the engine to stall.4) Crank the engine foran additional 10 seconds.

2. Disconnect the negative battery cable.3. Remove the rear seat. Refer to Section 9H, Seats.4. Remove the fuel pump access cover.5. Disconnect the electrical connector at the fuel

pump assembly.6. Disconnect the fuel outlet line.7. Disconnect the fuel tank return line.8. Turn the lock ring counterclockwise to clear the

tank tabs.9. Remove the fuel pump assembly from the tank.10. Remove and discard the gasket.

Installation Procedure1. Clean the gasket mating surface on the fuel tank.2. Position the new gasket in place.3. Install the fuel pump into the fuel tank in the same

location as removed for ease of line and connectorinstallation.

4. Position the lock ring in place and turn it clockwiseuntil it contacts the tank stop.

5. Connect the fuel pump assembly connector.6. Install the fuel pump outlet line.7. Install the fuel tank return line.8. Install the fuel pump access cover.9. Connect the negative battery cable.10. Perform an operational check of the fuel pump.11. Install the rear seat. Refer to Section 9H, Seats.

1F – 380IENGINE CONTROLS

DAEWOO V–121 BL4

FUEL TANK PRESSURE SENSOR

Removal Procedure

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and risk of personal injury or fire,it is necessary to relieve the fuel system pressure be-fore disconnecting the fuel lines.1. Relieve the fuel pressure. Refer to ” Fuel System

Pressure Relief ”in this section.2. Disconnect the negative battery cable.3. Remove the rear seat. Refer to Section 9H, Seats.4. Remove the fuel pump access cover.

5. Disconnect the fuel tank pressure sensor electricalconnector.

6. Bend the retaining tabs and remove the fuel tankpressure sensor.

Installation Procedure

1. Install the fuel tank pressure sensor and bend theretaining tabs into place.

2. Connect the fuel tank pressure sensor electricalconnector.

ENGINE CONTROLS 1F – 381

DAEWOO V–121 BL4

3. Install the fuel pump access cover.4. Install the rear seat. Refer to Section 9H, Seats.5. Install the fuel pump fuse and the gas cap.6. Connect the negative battery cable.

FUEL FILTER

Removal Procedure

Disconnect the negative battery cable.

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.

1. Relieve the fuel system pressure. Refer to ”FuelSystem Pressure Relief”in this section.

2. Disconnect the inlet/outlet fuel lines by moving theline connector lock forward and pulling the hose offof the fuel filter tube.

3. Remove the fuel filter mounting bracket assemblybolt.

4. Remove the fuel filter.

Installation Procedure1. Install the new fuel filter into the retaining clamp.

Note the flow direction.2. Install the outer fuel filter mounting bracket and the

mounting bracket assembly bolt.

TightenTighten the fuel filter mounting bracket assembly boltto 89 lb–in (10 Nm).

3. Connect the inlet/outlet lines. Secure the lines withthe connector lock.

4. Connect the negative battery cable.5. Perform a leak test of the fuel filter.

1F – 382IENGINE CONTROLS

DAEWOO V–121 BL4

FUEL RAIL AND INJECTORS

Removal Procedure

CAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.1. Relieve the fuel system pressure. Refer to ”Fuel

System Pressure Relief”in this section.2. Disconnect the negative battery cable.3. Disconnect the intake air temperature (IAT) sensor

connector.4. Disconnect the breather hose from the valve cover.

5. Remove the air intake tube and resonator.6. Disconnect the positive crankcase ventilation (PCV)

hose from the valve cover.7. Disconnect the throttle cables from the throttle body

and the bracket.8. Remove the fuel pressure regulator. Refer to ” Fuel

Pressure Regulator ” in this section.9. Disconnect the fuel return line at the fuel rail.10. Disconnect the fuel inlet line at the fuel rail.11. Remove the fuel rail retaining bolts.

Notice : Before removal, the fuel rail assembly may becleaned with a spray–type cleaner, following package in-structions. Do not immerse the fuel rails in liquid cleaningsolvent. Use care in removing the fuel rail assembly to pre-vent damage to the electrical connectors and the injectorspray tips. Prevent dirt and other contaminants from enter-ing open lines and passages. Fittings should be cappedand holes plugged during service.

Important : If an injector becomes separated from the railand remains in the cylinder head, replace the injector O–ring seals and the retaining clip.12. Remove the fuel rail with the fuel injector channel

cover and the injectors attached.13. Disconnect the fuel injector channel cover connec-

tors.

ENGINE CONTROLS 1F – 383

DAEWOO V–121 BL4

14. Remove the fuel injector retainer clips.15. Remove the fuel injectors by pulling them down and

out.16. Discard the fuel injector O–rings.

Installation Procedure

Important : Important: Different injectors are calibratedfor different flow rates. When ordering new fuel injectors,be certain to order the identical part number that is in-scribed on the old injector.1. Lubricate the new fuel injector O–rings with engine

oil. Install the new O–rings on the fuel injectors.2. Install the fuel injectors into the fuel rail sockets

with the fuel injector terminals facing outward.3. Install the fuel injector retaining clips onto the fuel

injector and the fuel rail ledge.4. Make sure that the retaining clip should be parallel

to the fuel injector harness connector.

5. Install the fuel rail assembly into the cylinder head.6. Install the fuel rail retaining bolts.

TightenTighten the fuel rail retaining bolts to 18 lb–ft (25Nm).

1F – 384IENGINE CONTROLS

DAEWOO V–121 BL4

7. Connect the fuel inlet line to the fuel rail.8. Connect the fuel return line to the fuel rail9. Install the fuel pressure regulator. Refer to ” Fuel

Pressure Regulator ” in this section.10. Connect the fuel injector channel cover and con-

nectors. Rotate each fuel injector as required.11. Connect the throttle cables to the throttle body

bracket.12. Connect the PCV hose to the valve cover.

13. Install the air intake tube.14. Connect the breather hose to the valve cover.15. Connect the IAT sensor connector.16. Connect the negative battery cable.17. Perform a leak check of the fuel rail and fuel injec-

tors.

FUEL PRESSURE REGULATORRemoval ProcedureCAUTION : The fuel system is under pressure. Toavoid fuel spillage and the risk of personal injury orfire, it is necessary to relieve the fuel system pressurebefore disconnecting the fuel lines.1. Relieve the fuel pressure. Refer to ” Fuel System

Pressure Relief”in this section.2. Disconnect the negative battery cable.3. Disconnect the intake air temperature (IAT) sensor

connector.4. Disconnect the breather hose from the valve cover.5. Remove the air intake tube.6. Disconnect the vacuum hose from the fuel pressure

regulator.7. Remove the fuel pressure regulator retaining

clamp.8. Remove the fuel pressure regulator by turning it

back and forth and then pulling it out.

ENGINE CONTROLS 1F – 385

DAEWOO V–121 BL4

9. Discard the O–ring.

Installation Procedure1. Lubricate a new O–ring. Install the new O–ring onto

the fuel pressure regulator body.2. Insert the fuel pressure regulator into the fuel rail

body.3. Install the fuel pressure regulator retaining clamp.

TightenTighten the fuel pressure regulator retaining clamp to106 lb–in (12 Nm).

4. Connect the vacuum hose to the fuel pressure re-gula–tor.

5. Install the air intake tube.6. Connect the breather hose to the valve cover.7. Connect the IAT sensor connector.8. Connect the negative battery cable.9. Perform a leak test of the fuel pressure regulator

with the engine off and the ignition ON.

ENGINE COOLANT TEMPERATURESENSOR

Removal Procedure1. Relieve the coolant system pressure.2. Disconnect the negative battery cable.3. Disconnect the engine coolant temperature (ECT)

sensor connector.Notice : Take care when handling the engine coolant tem-perature sensor. Damage to the sensor will affect the prop-er operation of the fuel injection system.4. Remove the ECT sensor from the electronic ignition

(EI) system ignition coil adapter.

Installation Procedure1. Coat the threads of the ECT sensor with sealer.2. Install the ECT sensor into the EI system ignition

coil adapter.

TightenTighten the engine coolant temperature sensor to 18lb–ft (25 Nm).

3. Connect the ECT sensor connector.4. Fill the coolant system.5. Connect the negative battery cable.

1F – 386IENGINE CONTROLS

DAEWOO V–121 BL4

THROTTLE POSITION SENSOR

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the throttle position (TP) sensor con-

nec–tor.3. Remove the TP sensor retaining bolts and the TP

sensor.

Installation Procedure1. With the throttle valve closed, position the TP sen-

sor on the throttle shaft. Align the TP sensor withthe bolt holes.

2. Install the TP sensor retaining bolts.

TightenTighten the throttle position sensor retaining bolts to18 lb–in (2 Nm).

3. Connect the TP sensor connector.4. Connect the negative battery cable.

THROTTLE BODY

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the intake air temperature (IAT) sensor

connector.3. Disconnect the breather hose from the valve cover.4. Remove the air intake tube.

ENGINE CONTROLS 1F – 387

DAEWOO V–121 BL4

5. Disconnect the throttle cables by opening thethrottle and moving the cable through the releaseslot.

6. Disconnect the vacuum hoses from the throttlebody.

7. Disconnect the Throttle Position (TP) sensor andthe Idle Air Control (IAC) valve connectors.

8. Disconnect the coolant hoses from the throttlebody.

9. Remove the throttle body retaining nuts.

Notice : Cover the opening of the intake manifold after re-moving the throttle body assembly. This will prevent anyobjects or debris from entering the engine which maycause damage.10. Remove the throttle body and discard the gasket.11. Remove the TP sensor. Refer to ” Throttle Position

Sensor ” in this section.12. Remove the IAC valve. Refer to ”Idle Air Control

Valve”in this section.

1F – 388IENGINE CONTROLS

DAEWOO V–121 BL4

Installation Procedure

Notice : Use care in cleaning old gasket material from ma-chined aluminum surfaces. Sharp tools may damage seal-ing surfaces.1. Clean the gasket mating surface on the intake

man–ifold.Notice : The throttle body may be cleaned following disas-sembly in a cold immersion–type cleaner. The TP sensorand the IAC valve should not come in contact with any sol-vent or cleaner, as they may be damaged.2. Clean the throttle body.3. Install the TP sensor. Refer to ” Throttle Position

Sensor ” in this section.4. Install the IAC valve. Refer to”Idle Air Control

Valve”in this section.5. Install the throttle body assembly with a new gasket

to the intake manifold.6. Install the throttle body retaining nuts.

TightenTighten the throttle body retaining nuts to 80 lb–in (9Nm).

7. Connect the TP sensor connector and the IACvalve connector.

8. Connect the coolant hoses to the throttle body.9. Connect the vacuum hoses to the throttle body.Important : Make sure the throttle/cruise control cablesdo not hold the throttle open. With the engine OFF, checkto see that the accelerator pedal is free.10. Connect the throttle/cruise cables.11. Install the air intake tube.12. Connect the breather hose to the valve cover.13. Connect the IAT sensor connector.14. Connect the negative battery cable.15. Fill the cooling system.

ENGINE CONTROLS 1F – 389

DAEWOO V–121 BL4

OXYGEN SENSOR

Removal Procedure1. Disconnect the negative battery cable.

Notice : The oxygen sensor (O2S 1) uses a permanentlyattached pigtail and connector. This pigtail should not beremoved from the O2S 1. Damage or removal of the pigtailor the connector could affect proper operation of the O2S1. Take care when handling the O2S 1. Do not drop ordamage the O2S1.

2. Disconnect the O2S 1 connector.

Notice : The oxygen sensor may be difficult to removewhen the engine temperature is below 118?F (48?C). Ex-cessive force may damage the threads in the exhaustmanifold.

3. Carefully remove the O2S 1 from the exhaust man-ifold.

Installation ProcedureImportant : A special anti–seize compound is used on theO2S 1 threads. This compound consists of a liquid graph-ite and glass beads. The graphite will burn away, but theglass beads will remain, making the sensor easier to re-move. New or service sensors will already have the com-pound applied to the threads. If a sensor is removed fromany engine and if for any reason it is to be reinstalled, thethreads must have anti–seize compound applied beforereinstallation.

1. Coat the threads of the O2S with an anti–seizecom–pound, if needed.

2. Install the O2S into the exhaust manifold.

TightenTighten the oxygen sensor to 41 NSm (30 lb–ft).

3. Connect the O2S connector.4. Connect the negative battery cable.

HEATED OXYGEN SENSOR

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the electrical connector.

1F – 390IENGINE CONTROLS

DAEWOO V–121 BL4

3. Remove the heated oxygen sensor (HO2S 2).

Installation Procedure

1. Install the HO2S 2.

TightenTighten the heated oxygen sensor to 30 lb–ft 41 Nm).

2. Connect the electrical connector.3. Connect the negative battery cable.

ENGINE CONTROLS 1F – 391

DAEWOO V–121 BL4

INTAKE AIR TEMPERATURESENSOR

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the intake air temperature (IAT) sensor

connector.3. Remove the IAT sensor by pulling it out of the air

in–take tube.

Installation Procedure1. Insert the IAT sensor into the air intake tube.2. Connect the IAT connector.3. Connect the negative battery cable.

IDLE AIR CONTROL VALVE

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the Idle Air Control (IAC) valve connec-

tor.3. Remove the IAC valve retaining bolts.Notice : On IAC valves that have been in service, do notpush on the valve pintle. The force required to move thepintle may damage the threads on the worm drive.4. Remove the IAC valve.5. Clean the IAC valve O–ring seal area, the pintle

valve seat and the air passage with a suitable fuelsystem cleaner. Do not use methyl ethyl ketone.

Installation Procedure

Important : If installing a new IAC valve, be sure to re-place it with an identical part. The IAC valve pintle shapeand diameter are designed for the specific application.Measure the distance between the tip of the IAC valvepintle and the mounting flange. If the distance is greaterthan 28 mm, use finger pressure to slowly retract thepintle. The force required to retract the pintlewill not dam-age the IAC valve. The purpose of the 28 mmsetting is toprevent the IAC pintle from bottoming out on the pintleseat. This 28 mm setting is also an adequate setting forcontrolled idle on a restart.1. Lubricate a new O–ring with engine oil. Install the

new O–ring onto the valve.2. Install the IAC valve into the throttle body.

1F – 392IENGINE CONTROLS

DAEWOO V–121 BL4

3. Install the IAC valve retaining bolts.

TightenTighten the idle air control valve retaining bolts to 27lb–in (3 Nm).

4. Connect the IAC valve connector.5. Connect the negative battery cable.6. Start the engine and check for the proper idle

speed.

MANIFOLD ABSOLUTE PRESSURESENSOR

Removal Procedure

1. Disconnect the negative battery cable.2. Disconnect the negative battery cable.3. Disconnect the Intake Air Temperature (IAT) sensor

connector.4. Disconnect the breather hose from the valve cover.

Remove the air intake tube.

5. Disconnect the throttle cable from the throttle bodyand bracket.

ENGINE CONTROLS 1F – 393

DAEWOO V–121 BL4

6. Remove the Manifold Absolute Pressure (MAP)sensor from the intake manifold.

7. Disconnect the MAP sensor harness from the MAPsensor.

Installation Procedure

1. Connect theMAP sensor harness to the MAP sen-sor.

2. Install the MAP sensor into the intake manifold.3. Connect the throttle cable to the throttle body and

bracket.

4. Install the air intake tube.5. Connect the breather hose to the valve cover.6. Connect the IAT sensor connector.7. Connect the negative battery cable.

1F – 394IENGINE CONTROLS

DAEWOO V–121 BL4

EXHAUST GAS RECIRCULATIONVALVE

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the Exhaust Gas Recirculation (EGR)

valve electrical connector.3. Remove the EGR valve retaining bolts.4. Remove the EGR valve from the Electronic Ignition

(EI) system ignition coil adapter.

Installation Procedure1. Clean the EI system ignition coil adapter mating

sur–face.2. Install a new EGR valve gasket.3. Install the EGR valve with the bolts.

TightenTighten the exhaust gas recirculation valve retainingbolts to 15 lb–ft (20 Nm).

4. Connect the EGR valve electrical connector.5. Connect the negative battery cable.

G SENSOR

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the G sensor electrical connector and

re–move the G sensor.

ENGINE CONTROLS 1F – 395

DAEWOO V–121 BL4

Installation Procedure1. Install the G sensor and connect the electrical con–

nector.2. Connect the negative battery cable.

EVAPORATIVE EMISSION CANISTER

Removal ProcedureCAUTION : Canister and vacuum hoses contain fuelvapors. Do not smoke in the area or permit an openflame.1. Remove the Evaporative (EVAP) Emission canister

rotective cover.2. Disconnect the canister fuel vapor hoses.3. Remove the bolt that secures the canister flange to

the vehicle.4. Slide canister out of the track holder.5. Remove the canister.

Installation Procedure1. Insert the canister into the track and slide it into

posi–tion.2. Install the canister flange bolt.

TightenTighten the evaporative emission canister flange boltto 20 Nm(15 lb–ft).

3. Connect the canister fuel vapor hoses.4. Install the canister protective cover.

TightenTighten the evaporative emission canister protectivecover to 71 lb–in (8 Nm).

1F – 396IENGINE CONTROLS

DAEWOO V–121 BL4

EVAPORATIVE EMISSION CANISTERPURGE SOLENOID

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the Evaporative (EVAP) Emission can-

ister purge solenoid connector.3. Disconnect the vacuum hoses from the EVAP emis-

sion canister purge solenoid.4. Remove the EVAP emission canister purge sole-

noid bracket bolt from the intake manifold.5. Unclip the EVAP emission canister purge solenoid

from the mounting bracket.

Installation Procedure1. Attach the EVAP canister purge solenoid to the

mounting bracket.2. Install the EVAP canister purge solenoid and the

mounting bracket to the intake manifold with thebracket bolt.

TightenTighten the evaporative emission canister purgesole–noid bracket bolt to 44 lb–in (5 Nm).

3. Connect the vacuum hoses to the EVAP emissioncanister purge solenoid.

4. Connect the EVAP emission canister purge sole-noid connector.

5. Connect the negative battery cable.

CRANKSHAFT POSITION SENSOR

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the power steering pump, if equipped. Re-

fer to Section 6B, Power Steering Pump.3. Remove the A/C compressor, if equipped. Refer to

Section 7B, Manual Control Heating, Ventilation,and Air Conditioning System.

4. Remove the rear A/C compressor mounting bracketbolts and the rear A/C compressor mounting brack-et, if equipped.

5. Remove the accessory mounting bracket by remov-ing the bolts.

ENGINE CONTROLS 1F – 397

DAEWOO V–121 BL4

6. Disconnect the Crankshaft Position (CKP) sensorconnector from the fuel injector channel cover.

7. Remove the CKP sensor retaining bolt.8. Gently rotate and remove the CKP sensor from the

engine block.

Installation Procedure

1. Insert the CKP sensor into the engine block.2. Install the CKP sensor retaining bolt.

TightenTighten the crankshaft position sensor retaining boltto 89 lb–in (10 Nm).

3. Connect the CKP sensor connector to the fuel in-jector channel cover.

4. Install the accessory mounting bracket.

TightenTighten the accessory mounting bracket bolts to 35Nm (26 lb–ft).

5. Install the rear A/C mounting bracket, if equipped.

TightenTighten the rear A/C mounting bracket bolts to 26 lb–ft(35 Nm).

6. Install the A/C compressor, if equipped. Refer toSection 7B, Manual Control Heating, Ventilation,and Air Conditioning System.

7. Install the power steering pump, if equipped. RefertoSection 6B, Power Steering Pump.

8. Connect the negative battery cable.

1F – 398IENGINE CONTROLS

DAEWOO V–121 BL4

CAMSHAFT POSITION SENSOR

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the engine cover.3. Disconnect the sensor electrical connector.

4. Remove the timing belt front cover. Refer to Sec-tion 1C, DOHC Engine Mechanical.

5. Remove the camshaft position sensor bolts.6. Remove the camshaft position sensor from the top.

Installation Procedure

1. Install the camshaft position sensor and bolts.

TightenTighten the camshaft position sensor bolts to 12 Nm(106 lb–in).

ENGINE CONTROLS 1F – 399

DAEWOO V–121 BL4

2. Install the timing belt front cover, the crankshaftpulley, the accessory drive belt, and the air filter.Refer to Section 1C, DOHC Engine Mechanical.

3. Connect the sensor electrical connector.4. Install the engine cover.5. Connect the negative battery cable.

POWERTRAIN CONTROL MODULE/ENGINE CONTROL MODULE

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the right side kick panel. Refer to Section

9G, Interior Trim.3. Disconnect the powertrain control module

(PCM)/engine control module (ECM) retaining clipfrom the PCM/ECM mounting base.

4. Remove the retaining clip lower end from themounting base.

5. Remove the PCM/ECM from the mounting base.6. Disconnect the PCM/ECM connectors from the

PCM/ ECM.

1F – 400IENGINE CONTROLS

DAEWOO V–121 BL4

Installation Procedure1. Connect the PCM/ECM connectors to the PCM/

ECM.2. Insert and align the PCM/ECM into the mounting

base.3. Insert the retaining clip lower end into the mounting

base.4. Connect the retaining clip to the mounting base.5. Install the passenger side kick panel. Refer to Sec-

tion 9G, Interior Trim.6. Connect the negative battery cable.7. Perform a crankshaft position system variation

learning procedure. Refer to ” DTC P1336 ” in thissection.

ELECTRONIC IGNITION SYSTEMIGNITION COIL

Removal Procedure1. Disconnect the negative battery cable.2. Disconnect the electronic ignition (EI) system igni-

tion coil connector.3. Note the ignition wire location and remove the igni-

tion wires.4. Remove the EI system ignition coil retaining bolts.5. Remove the EI system ignition coil.

Installation Procedure1. Install the EI system ignition coil into the mounting

location and install the retaining bolts.

TightenTighten the electronic ignition system ignition coil re–taining bolts to 89 lb–in (10 Nm).

2. Connect the EI system ignition coil connector.3. Install the ignition wires.4. Connect the negative battery cable.

ENGINE CONTROLS 1F – 401

DAEWOO V–121 BL4

FUEL CUTOFF SWITCH

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the passenger front rocker trim panel. Re-

fer to Section 9G, Interior Trim.3. Remove the lower B–pillar trim panel. Refer to Sec-

tion 9G, Interior Trim.4. Reposition the carpet.

5. Remove the fuel cutoff switch mounting bolts.6. Disconnect the electrical connector at the fuel cutoff

switch.

Installation Procedure

1. Connect the electrical connector at the fuel cutoffswitch.

2. Install the fuel cutoff switch mounting bolts.

TightenTighten the fuel cutoff switch mounting bolts to 27 lb–in (3 Nm).

1F – 402IENGINE CONTROLS

DAEWOO V–121 BL4

3. Reposition the carpet.4. Install the lower B–pillar trim panel. Refer to Sec-

tion 9G, Interior Trim.5. Install the passenger front rocker trim panel. Refer

to Section 9G, Interior Trim.6. Connect the negative battery cable.Important : The fuel cutoff switch may have to be reset toenable the vehicle to start.

KNOCK SENSOR

Removal Procedure

1. Disconnect the negative battery cable.2. Remove the intake manifold. Refer toSection 1C,

DOHC Engine Mechanical.3. Disconnect the electrical connector at the Knock

Sensor (KS).

4. Remove the KS.

ENGINE CONTROLS 1F – 403

DAEWOO V–121 BL4

Installation Procedure

1. Install the KS.

TightenTighten the knock sensor bolt to 15 lb–ft (20 Nm).

2. Connect the electrical connector at the KS.3. Remove the intake manifold. Refer toSection 1C,

DOHC Engine Mechanical.4. Connect the negative battery cable.

1F – 404IENGINE CONTROLS

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

IGNITION SYSTEM OPERATIONThis ignition system does not use a conventional distribu-tor and coil. It uses a crankshaft position sensor input tothe powertrain control module (PCM)/engine control mod-ule (ECM). The PCM/ECM then determines ElectronicSpark Timing (EST) and triggers the direct ignition systemignition coil.

This type of distributorless ignition system uses a ”wastespark” method of spark distribution. Each cylinder ispaired with the cylinder that is opposite it (1–4 or 2–3). Thespark occurs simultaneously in the cylinder coming up onthe compression stroke and in the cylinder coming up onthe exhaust stroke. The cylinder on the exhaust stroke re-quires very little of the available energy to fire the sparkplug. The remaining energy is available to the spark plugin the cylinder on the compression stroke.

These systems use the EST signal from the PCM/ECM tocontrol the electronic spark timing. The PCM/ECM usesthe following information:

Engine load (manifold pressure or vacuum). Atmospheric (barometric) pressure. Engine temperature. Intake air temperature. Crankshaft position. Engine speed (rpm).

ELECTRONIC IGNITION SYSTEMIGNITION COILThe Electronic Ignition (EI) system ignition coil providesthe spark for two spark plugs simultaneously. The EI sys-tem ignition coil is not serviceable and must be replacedas an assembly.

CRANKSHAFT POSITION SENSORThis direct ignition system uses a magnetic crankshaftposition sensor. This sensor protrudes through its mountto within approximately 0.05 inch (1.3 mm) of the crank-shaft reluctor. The reluctor is a special wheel attached tothe crankshaft or crankshaft pulley with 58 slots machinedinto it, 57 of which are equally spaced in 6 degree intervals.The last slot is wider and serves to generate a ”syncpulse.” As the crankshaft rotates, the slots in the reluctorchange the magnetic field of the sensor, creating an in-duced voltage pulse. The longer pulse of the 58th slotidentifies a specific orientation of the crankshaft and al-lows the powertrain control module (PCM)/engine controlmodule (ECM) to determine the crankshaft orientation atall times. The PCM/ECM uses this information to generatetimed ignition and injection pulses that it sends to the igni-tion coils and to the fuel injectors.

CAMSHAFT POSITION SENSORThe Camshaft Position (CMP) sensor sends a CMP sen-sor signal to the powertrain control module (PCM)/enginecontrol module (ECM). The PCM/ECM uses this signal asa ”sync pulse” to trigger the injectors in the proper se-quence. The PCM/ECM uses the CMP sensor signal to in-dicate the position of the #1 piston during its power stroke.This allows the PCM/ECM to calculate true sequential fuelinjection mode of operation. If the PCM/ECM detects anincorrect CMP sensor signal while the engine is running,DTC P0341 will set. If the CMP sensor signal is lost whilethe engine is running, the fuel injection system will shift toa calculated sequential fuel injection mode based on thelast fuel injection pulse, and the engine will continue to run.As long as the fault is present, the engine can be restarted.It will run in the calculated sequential mode with a 1–in–6chance of the injector sequence being correct.

IDLE AIR SYSTEM OPERATIONThe idle air system operation is controlled by the base idlesetting of the throttle body and the Idle Air Control (IAC)valve.

The powertrain control module (PCM)/engine controlmodule (ECM) uses the IAC valve to set the idle speed de-pendent on conditions. The PCM/ECM uses informationfrom various inputs, such as coolant temperature, man-ifold vacuum, etc., for the effective control of the idlespeed.

FUEL CONTROL SYSTEMOPERATIONThe function of the fuel metering system is to deliver thecorrect amount of fuel to the engine under all operatingconditions. The fuel is delivered to the engine by the indi-vidual fuel injectors mounted into the intake manifold neareach cylinder.

The two main fuel control sensors are the manifold abso-lute pressure (MAP) sensor and the oxygen sensor O2S1).

The MAP sensor measures or senses the intake manifoldvacuum. Under high fuel demands the MAP sensor readsa low vacuum condition, such as wide open throttle. Thepowertrain control module (PCM)/engine control module(ECM) uses this information to richen the mixture, thus in-creasing the fuel injector on–time, to provide the correctamount of fuel. When decelerating, the vacuum in-creases. This vacuum change is sensed by the MAP sen-sor and read by the PCM/ECM, which then decreases thefuel injector on–time due to the low fuel demand condi-tions.

The O2S sensor is located in the exhaust manifold. TheO2S sensor indicates to the PCM/ECM the amount of oxy-gen in the exhaust gas and the PCM/ECM changes the air/fuel ratio to the engine by controlling the fuel injectors. Thebest air/fuel ratio to minimize exhaust emissions is 14.7 to1, which allows the catalytic converter to operate most effi-

ENGINE CONTROLS 1F – 405

DAEWOO V–121 BL4

ciently. Because of the constant measuring and adjustingof the air/fuel ratio, the fuel injection system is called a”closed loop” system.

The PCM/ECM uses voltage inputs from several sensorsto determine how much fuel to provide to the engine. Thefuel is delivered under one of several conditions, called”modes.”

Starting Mode

When the ignition is turned ON, the PCM/ECM turns thefuel pump relay on for two seconds. The fuel pump thenbuilds fuel pressure. The PCM/ECM also checks the En-gine Coolant Temperature (ECT) sensor and the ThrottlePosition (TP) sensor and determines the proper air/fuel ra-tio for starting the engine. This ranges from 1.5 to 1 at–97³F (–36³C) coolant temperature to 14.7 to 1 at 201³F(94³C) coolant temperature. The PCM/ECM controls theamount of fuel delivered in the starting mode by changinghow long the fuel injector is turned on and off. This is doneby ”pulsing” the fuel injectors for very short times.

Clear Flood Mode

If the engine floods with excessive fuel, it may be clearedby pushing the accelerator pedal down all the way. ThePCM/ECM will then completely turn off the fuel by eliminat-ing any fuel injector signal. The PCM/ECM holds this injec-tor rate as long as the throttle stays wide open and the en-gine is below approximately 400. If the throttle positionbecomes less than approximately 80 percent, the PCM/ECM returns to the starting mode.

Run Mode

The run mode has two conditions called ”open loop” and”closed loop.”

Open Loop

When the engine is first started and it is above 400 rpm,the system goes into ”open loop” operation. In ”open loop,”the PCM/ECM ignores the signal from the O2S and calcu-lates the air/fuel ratio based on inputs from the ECT sensorand the MAP sensor. The sensor stays in ”open loop” untilthe following conditions are met:

The O2S sensor has a varying voltage output,showing that it is hot enough to operate properly.

The ECT sensor is above a specified temperature. A specific amount of time has elapsed after starting

the engine.

Closed Loop

The specific values for the above conditions vary with dif-ferent engines and are stored in the Electronically Eras-able Programmable Read–Only Memory (EEPROM).When these conditions are met, the system goes into”closed loop” operation. In ”closed loop,” the PCM/ECMcalculates the air/fuel ratio (fuel injector ontime) based onthe signal from the oxygen sensor. This allows the air/fuelratio to stay very close to 14.7 to 1.

Acceleration ModeThe PCM/ECM responds to rapid changes in throttle posi-tion and airflow and provides extra fuel.

Deceleration ModeThe PCM/ECM responds to changes in throttle positionand airflow and reduces the amount of fuel. When decel-eration is very fast, the PCM/ECM can cut off fuel com-pletely for short periods of time.

Battery Voltage Correction ModeWhen battery voltage is low, the PCM/ECM can compen-sate for a weak spark delivered by the ignition module byusing the following methods:

Increasing the fuel injector pulse width. Increasing the idle speed rpm. Increasing the ignition dwell time.

Fuel Cut–Off ModeNo fuel is delivered by the fuel injectors when the ignitionis OFF. This prevents dieseling or engine run–on. Also, thefuel is not delivered if there are no reference pulses re-ceived from the central power supply. This prevents flood-ing.

EVAPORATIVE EMISSION CONTROLSYSTEM OPERATIONThe basic Evaporative (EVAP) Emission control systemused is the charcoal canister storage method. This meth-od transfers fuel vapor from the fuel tank to an activatedcarbon (charcoal) storage device (canister) to hold the va-pors when the vehicle is not operating. When the engineis running, the fuel vapor is purged from the carbon ele-ment by intake airflow and consumed in the normal com-bustion process.

Gasoline vapors from the fuel tank flow into the tube la-beled TANK. These vapors are absorbed into the carbon.The canister is purged by the powertrain control module(PCM)/engine control module (ECM) when the engine hasbeen running for a specified amount of time. Air is drawninto the canister and mixed with the vapor. This mixture isthen drawn into the intake manifold.

The PCM/ECM supplies a ground to energize the EVAPemission canister purge solenoid valve. This valve is Pul-seWidth Modulated (PWM) or turned on and off severaltimes a second. The EVAP emission canister purge PWMduty cycle varies according to operating conditions deter-mined by mass airflow, fuel trim, and intake air tempera-ture.

Poor idle, stalling, and poor driveability can be caused bythe following conditions:

An inoperative EVAP emission canister purge sole-noid valve.

A damaged canister. Hoses that are split, cracked, or not connected to

the proper tubes.

1F – 406IENGINE CONTROLS

DAEWOO V–121 BL4

EVAPORATIVE EMISSION CANISTERThe Evaporative (EVAP) Emission canister is an emissioncontrol device containing activated charcoal granules.The EVAP emission canister is used to store fuel vaporsfrom the fuel tank. Once certain conditions are met, thepowertrain control module (PCM)/engine control module(ECM) activates the EVAP canister purge solenoid, allow-ing the fuel vapors to be drawn into the engine cylindersand burned.

POSITIVE CRANKCASEVENTILATION CONTROL SYSTEMOPERATIONA Positive Crankcase Ventilation (PCV) system is used toprovide complete use of the crankcase vapors. Fresh airfrom the air cleaner is supplied to the crankcase. The freshair is mixed with blowby gases which are then passedthrough a vacuum hose into the intake manifold.

Periodically inspect the hoses and the clamps. Replaceany crankcase ventilation components as required.

A restricted or plugged PCV hose may cause the followingconditions:

Rough idle Stalling or low idle speed Oil leaks Oil in the air cleaner Sludge in the engine

A leaking PCV hose may cause the following conditions:

Rough idle Stalling High idle speed

ENGINE COOLANT TEMPERATURESENSORThe Engine Coolant Temperature (ECT) sensor is athermistor (a resistor which changes value based on tem-perature) mounted in the engine coolant stream. Low cool-ant temperature produces a high resistance (100,000ohms at –40³F [–40³C]) while high temperature causeslow resistance (70 ohms at 266³F [130³C]).

The powertrain control module (PCM)/engine controlmodule (ECM) supplies 5 volts to the ECT sensor througha resistor in the PCM/ECM and measures the change involtage. The voltage will be high when the engine is cold,and low when the engine is hot. By measuring the changein voltage, the PCM/ECM can determine the coolant tem-perature. The engine coolant temperature affects most ofthe systems that the PCM/ECM controls. A failure in theECT sensor circuit should set a diagnostic trouble codeP0117 or P0118. Remember, these diagnostic troublecodes indicate a failure in the ECT sensor circuit, so prop-er use of the chart will lead either to repairing a wiring prob-lem or to replacing the sensor to repair a problem properly.

THROTTLE POSITION SENSORThe Throttle Position (TP) sensor is a potentiometer con-nected to the throttle shaft of the throttle body. The TP sen-sor electrical circuit consists of a 5 volt supply line and aground line, both provided by the powertrain control mod-ule (PCM)/engine control module (ECM). The PCM/ECMcalculates the throttle position by monitoring the voltageon this signal line. The TP sensor output changes as theaccelerator pedal is moved, changing the throttle valveangle. At a closed throttle position, the output of the TPsensor is low, about 0.5 volt. As the throttle valve opens,the output increases so that, at Wide Open Throttle(WOT), the output voltage will be about 5 volts.

The PCM/ECM can determine fuel delivery based onthrottle valve angle (driver demand). A broken or loose TPsensor can cause intermittent bursts of fuel from the injec-tor and an unstable idle, because the PCM/ECM thinks thethrottle is moving. A problem in any of the TP sensor cir-cuits should set a diagnostic trouble code (DTC) P0121 orP0122. Once the DTC is set, the PCM/ECM will substitutea default value for the TP sensor and some vehicle perfor-mance will return. A DTC P0121 will cause a high idlespeed.

CATALYST MONITOR OXYGENSENSORSThree–way catalytic converters are used to control emis-sions of hydrocarbons (HC), carbon monoxide (CO), andoxides of nitrogen (NOx). The catalyst within the convert-ers promotes a chemical reaction. This reaction oxidizesthe HC and CO present in the exhaust gas and convertsthem into harmless water vapor and carbon dioxide. Thecatalyst also reduces NOx by converting it to nitrogen. Thepowertrain control module (PCM)/engine control module(ECM) can monitor this process using the Bank 1 Sensor1 and Bank 1 Sensor 2 sensors. These sensors producean output signal which indicates the amount of oxygenpresent in the exhaust gas entering and leaving the three–way converter. This indicates the catalyst’s ability to effi-ciently convert exhaust gasses. If the catalyst is operatingefficiently, the Bank 1 Sensor 1 sensor signals will be moreactive than the signals produced by the Bank 1 Sensor 2sensor. The catalyst monitor sensors operate the sameway as the fuel control sensors. The sensor’s main func-tion is catalyst monitoring, but they also have a limited rolein fuel control. If a sensor output indicates a voltage eitherabove or below the 450 mv bias voltage for an extendedperiod of time, the PCM/ECM will make a slight adjust-ment to fuel trim to ensure that fuel delivery is correct forcatalyst monitoring.

A problem with the Bank 1 Sensor 1 sensor circuit will setDTC P0131, P0132, P0133 or P0134 depending, on thespecial condition. A problem with the Bank 1 Sensor 2 sen-sor signal will set DTC P0137, P0138, P0140 or P0141,depending on the special condition.

ENGINE CONTROLS 1F – 407

DAEWOO V–121 BL4

A fault in the heated oxygen sensor (HO2S) heater ele-ment or its ignition feed or ground will result in lower oxy-gen sensor response. This may cause incorrect catalystmonitor diagnostic results.

EXHAUST GAS RECIRCULATIONVALVEThe Exhaust Gas Recirculation (EGR) system is used onengines equipped with an automatic transaxle to lowerNOx (oxides of nitrogen) emission levels caused by highcombustion temperature. The EGR valve is controlled bythe powertrain control module (PCM)/engine control mod-ule (ECM). The EGR valve feeds small amounts of ex-haust gas into the intake manifold to decrease combustiontemperature. The amount of exhaust gas recirculated iscontrolled by variations in vacuum and exhaust back pres-sure. If too much exhaust gas enters, combustion will nottake place. For this reason, very little exhaust gas is al-lowed to pass through the valve, especially at idle.

The EGR valve is usually open under the following condi-tions:

Warm engine operation. Above idle speed.

Results of Incorrect Operation

Too much EGR flow tends to weaken combustion, causingthe engine to run roughly or to stop. With too much EGRflow at idle, cruise, or cold operation, any of the followingconditions may occur:

The engine stops after a cold start. The engine stops at idle after deceleration. The vehicle surges during cruise. Rough idle.

If the EGR valve stays open all the time, the engine maynot idle. Too little or no EGR flow allows combustion tem-peratures to get too high during acceleration and load con-ditions. This could cause the following conditions:

Spark knock (detonation) Engine overheating Emission test failure

INTAKE AIR TEMPERATURESENSORThe Intake Air Temperature (IAT) sensor is a thermistor,a resistor which changes value based on the temperatureof the air entering the engine. Low temperature producesa high resistance (4,500 ohms at –40³F [–40³C]), whilehigh temperature causes a low resistance (70 ohms at266³F [130³C]).

The powertrain control module (PCM)/engine controlmodule (ECM) provides 5 volts to the IAT sensor througha resistor in the PCM/ECM and measures the change involtage to determine the IAT. The voltage will be high when

the manifold air is cold and low when the air is hot. ThePCM/ECM knows the intake IAT by measuring the volt-age.

The IAT sensor is also used to control spark timing whenthe manifold air is cold.

A failure in the IAT sensor circuit sets a diagnostic troublecode P0112 or P0113.

IDLE AIR CONTROL VALVENotice : Do not attempt to remove the protective cap toreadjust the stop screw. Misadjustment may result in dam-age to the Idle Air Control (IAC) valve or to the throttlebody.

The IAC valve is mounted on the throttle body where itcontrols the engine idle speed under the command of thepowertrain control module (PCM)/engine control module(ECM). The PCM/ECM sends voltage pulses to the IACvalve motor windings, causing the IAC valve pintle tomovein or out a given distance (a step or count) for each pulse.The pintle movement controls the airflow around thethrottle valves which, in turn, control the engine idle speed.

The desired idle speeds for all engine operating conditionsare programmed into the calibration of the PCM/ECM.These programmed engine speeds are based on the cool-ant temperature, the park/neutral position switch status,the vehicle speed, the battery voltage, and the A/C systempressure (if equipped).

The PCM/ECM ”learns” the proper IAC valve positions toachieve warm, stabilized idle speeds (rpm) desired for thevarious conditions (park/neutral or drive, A/C on or off, ifequipped). This information is stored in PCM/ECM ”keepalive” memories. Information is retained after the ignitionis turned OFF. All other IAC valve positioning is calculatedbased on these memory values. As a result, engine varia-tions due to wear and variations in the minimum throttlevalve position (within limits) do not affect engine idlespeeds. This system provides correct idle control under allconditions. This also means that disconnecting power tothe PCM/ECM can result in incorrect idle control or thenecessity to partially press the accelerator when startinguntil the PCM/ECM relearns idle control.

Engine idle speed is a function of total airflow into the en-gine based on the IAC valve pintle position, the throttlevalve opening, and the calibrated vacuum loss through ac-cessories. The minimum throttle valve position is set at thefactory with a stop screw. This setting allows enough air-flow by the throttle valve to cause the IAC valve pintle tobe positioned a calibrated number of steps (counts) fromthe seat during ”controlled” idle operation. The minimumthrottle valve position setting on this engine should not beconsidered the ”minimum idle speed,” as on other fuel in-jected engines. The throttle stop screw is covered with aplug at the factory following adjustment.

If the IAC valve is suspected as the cause of improper idlespeed, refer to ”Idle Air Control System Check” in this sec-tion.

1F – 408IENGINE CONTROLS

DAEWOO V–121 BL4

MANIFOLD ABSOLUTE PRESSURESENSORThe Manifold Absolute Pressure (MAP) sensor measuresthe changes in the intake manifold pressure which resultfrom engine load and speed changes. It converts these toa voltage output.

A closed throttle on engine coast down produces a rela-tively low MAP output. MAP is the opposite of vacuum.When manifold pressure is high, vacuum is low. The MAPsensor is also used to measure barometric pressure. Thisis performed as part of MAP sensor calculations. With the

ignition ON and the engine not running, the powertraincontrol module (PCM)/engine control module (ECM) willread the manifold pressure as barometric pressure andadjust the air/fuel ratio accordingly. This compensation foraltitude allows the system to maintain driving performancewhile holding emissions low. The barometric function willupdate periodically during steady driving or under a wideopen throttle condition. In the case of a fault in the baro-metric portion of the MAP sensor, the PCM/ECM will setto the default value.

A failure in the MAP sensor circuit sets a diagnostic troublecode P0107 or P0108.

The following tables show the difference between absolute pressure and vacuum related to MAP sensor output, whichappears as the top row of both tables.

MAP

Volts 4.9 4.4 3.8 3.3 2.7 2.2 1.7 1.1 0.6 0.3 0.3

kPa 100 90 80 70 60 50 40 30 20 10 0

in. Hg 29.6 26.6 23.7 20.7 17.7 14.8 11.8 8.9 5.9 2.9 0

VACUUM

Volts 4.9 4.4 3.8 3.3 2.7 2.2 1.7 1.1 0.6 0.3 0.3

kPa 0 10 20 30 40 50 60 70 80 90 100

in. Hg 0 2.9 5.9 8.9 11.8 14.8 17..7 20.7 23.7 26.7 29.6

POWERTRAIN CONTROLMODULE/ENGINE CONTROLMODULEThe powertrain control module (PCM)/engine controlmodule (ECM), located inside the passenger kick–panel,is the control center of the fuel injection system. Itconstantly looks at the information from various sensorsand controls the systems that affect the vehicle’s perfor-mance. The PCM/ECM also performs the diagnostic func-tions of the system. It can recognize operational problems,alert the driver through the Malfunction Indicator Lamp(MIL), and store diagnostic trouble code(s) which identifyproblem areas to aid the technician in making repairs.

There are no serviceable parts in the PCM/ECM. The cal-ibrations are stored in the PCM/ECM in the ProgrammableRead–Only Memory (PROM).

The PCM/ECM supplies either 5 or 12 volts to power thesensors or switches. This is done through resistances inthe PCM/ECM which are so high in value that a test lightwill not come on when connected to the circuit. In somecases, even an ordinary shop voltmeter will not give an ac-curate reading because its resistance is too low. You mustuse a digital voltmeter with a 10 megohm input impedanceto get accurate voltage readings. The PCM/ECM controlsoutput circuits such as the fuel injectors, the idle air control

valve, the A/C clutch relay, etc., by controlling the groundcircuit through transistors or a device called a ”quad–driv-er.”

FUEL INJECTORThe Multiport Fuel Injection (MFI) assembly is a solenoid–operated device controlled by the powertrain control mod-ule (PCM)/engine control module (ECM). It meters pres-surized fuel to a single engine cylinder. The PCM/ECMenergizes the fuel injector or the solenoid to a normallyclosed ball or pintle valve. This allows fuel to flow into thetop of the injector, past the ball or pintle valve, and througha recessed flow director plate at the injector outlet.

The director plate has six machined holes that control thefuel flow, generating a conical spray pattern of finely atom-ized fuel at the injector tip. Fuel from the tip is directed atthe intake valve, causing it to become further atomizedand vaporized before entering the combustion chamber.A fuel injector which is stuck partially open will cause a lossof fuel pressure after the engine is shut down. Also, an ex-tended crank time will be noticed on some engines. Diesel-ing can also occur because some fuel can be delivered tothe engine after the ignition is turned OFF.

KNOCK SENSORThe knock sensor detects abnormal knocking in the en-gine. The sensor is mounted in the engine block near thecylinders. The sensor produces an AC output voltagewhich increases with the severity of the knock. This signal

ENGINE CONTROLS 1F – 409

DAEWOO V–121 BL4

is sent to the powertrain control module (PCM)/enginecontrol module (ECM). The PCM/ECM then adjusts theignition timing to reduce the spark knock.

G SENSORThe powertrain control module (PCM)/engine controlmodule (ECM) receives rough road information from theG sensor. The PCM/ECM uses the rough road informationto enable or disable the misfire diagnostic. The misfirediagnostic can be greatly affected by crankshaft speedvariations caused by driving on rough road surfaces. TheG sensor generates rough road information by producinga signal which is proportional to the movement of a smallmetal bar inside the sensor.

If a fault occurs which causes the PCM/ECM to not receiverough road information between 30 and 80 mph (50 and132 km/h), DTC P1391 will set.

FUEL CUTOFF SWITCHThe fuel cutoff switch is a safety device. In the event of acollision or sudden impact, it automatically cuts off the fuelsupply and activates the door lock relay. After the switchhas been activated, it must be reset in order to restart theengine. To reset this fuel–cutoff feature, press the rubbertop of the switch located near the left side of the driver’sseat.

STRATEGY–BASED DIAGNOSTICS

Strategy–Based DiagnosticsThe strategy–based diagnostic is a uniform approach torepair all Electrical/Electronic (E/E) systems. The diag-nostic flow can always be used to resolve an E/E systemproblem and is a starting point when repairs are neces-sary. The following steps will instruct the technician onhow to proceed with a diagnosis:

Verify the customer complaint. To verify the cus-tomer complaint, the technician should know thenormal operation of the system.

Perform preliminary checks as follows:

Conduct a thorough visual inspection. Review the service history. Detect unusual sounds or odors. Gather Diagnostic Trouble Code (DTC) informa-

tion to achieve an effective repair.

Check bulletins and other service information. Thisincludes videos, newsletters, etc.

Refer to service information (manual) systemcheck(s).

Refer to service diagnostics.

No Trouble FoundThis condition exists when the vehicle is found to operatenormally. The condition described by the customer may benormal. Verify the customer complaint against another ve-

hicle that is operating normally. The condition may be in-termittent. Verify the complaint under the conditions de-scribed by the customer before releasing the vehicle.

Re–examine the complaint.

When the complaint cannot be successfully found or iso-lated, a re–evaluation is necessary. The complaint shouldbe re–verified and could be intermittent as defined in ”In-termittents,” or could be normal.

After isolating the cause, the repairs should be made. Vali-date for proper operation and verify that the symptom hasbeen corrected. This may involve road testing or othermethods to verify that the complaint has been resolved un-der the following conditions:

Conditions noted by the customer. If a DTC was diagnosed, verify a repair by duplicat-

ing conditions present when the DTC was set asnoted in the Failure Records or Freeze Frame data.

Verifying Vehicle RepairVerification of the vehicle repair will be more comprehen-sive for vehicles with On–Board Diagnostic (OBD II) sys-tem diagnostics. Following a repair, the technician shouldperform these steps:

Important : Follow the steps below when you verify re-pairs on OBD II systems. Failure to follow these stepscould result in unnecessary repairs.

Review and record the Failure Records and theFreeze Frame data for the DTC which has beendiagnosed (Freeze Fame data will only be storedfor an A or B type diagnostic and only if the MILhas been requested).

Clear the DTC(s). Operate the vehicle within conditions noted in the

Failure Records and Freeze Frame data. Monitor the DTC status information for the specific

DTC which has been diagnosed until the diagnostictest associated with that DTC runs.

OBD II SERVICEABILITY ISSUESBased on the knowledge gained from On–Board Diagnos-tic (OBD II) experience in the 1994 and 1995 model years,this list of non–vehicle faults that could affect the perfor-mance of the OBD II system has been compiled. Thesenon–vehicle faults vary from environmental conditions tothe quality of fuel used. With the introduction of OBD IIdiagnostics across the entire passenger car and light–dutytruck market in 1996, illumination of the MIL due to a non–vehicle fault could lead to misdiagnosis of the vehicle, in-creased warranty expense and customer dissatisfaction.The following list of non–vehicle faults does not include ev-ery possible fault and may not apply equally to all productlines.

Fuel QualityFuel quality is not a new issue for the automotive industry,but its potential for turning on the Malfunction IndicatorLamp (MIL) with OBD II systems is new.

1F – 410IENGINE CONTROLS

DAEWOO V–121 BL4

Fuel additives such as ”dry gas” and ”octane enhancers”may affect the performance of the fuel. If this results in anincomplete combustion or a partial burn, it will set DTCP0300. The Reed Vapor Pressure of the fuel can alsocreate problems in the fuel system, especially during thespring and fall months when severe ambient temperatureswings occur. A high Reed Vapor Pressure could show upas a Fuel Trim DTC due to excessive canister loading.High vapor pressures generated in the fuel tank can alsoaffect the Evaporative Emission diagnostic as well.

Using fuel with the wrong octane rating for your vehiclemay cause driveability problems. Many of the major fuelcompanies advertise that using ”premium” gasoline willimprove the performance of your vehicle. Most premiumfuels use alcohol to increase the octane rating of the fuel.Although alcohol–enhanced fuels may raise the octanerating, the fuel’s ability to turn into vapor in cold tempera-tures deteriorates. This may affect the starting ability andcold driveability of the engine.

Low fuel levels can lead to fuel starvation, lean engine op-eration, and eventually engine misfire.

Non–OEM PartsAll of the OBD II diagnostics have been calibrated to runwith Original Equipment Manufacturer (OEM) parts.Something as simple as a high–performance exhaust sys-tem that affects exhaust system back pressure could po-tentially interfere with the operation of the Exhaust GasRecirculation (EGR) valve and thereby turn on the MIL.Small leaks in the exhaust system near the post catalystoxygen sensor can also cause the MIL to turn on.

Aftermarket electronics, such as cellular phones, stereos,and anti–theft devices, may radiate electromagnetic inter-ference (EMI) into the control system if they are improperlyinstalled. This may cause a false sensor reading and turnon the MIL.

EnvironmentTemporary environmental conditions, such as localizedflooding, will have an effect on the vehicle ignition system.If the ignition system is rain–soaked, it can temporarilycause engine misfire and turn on the MIL.

RefuelingA new OBD II diagnostic checks the integrity of the entireEvaporative (EVAP) Emission system. If the vehicle is re-started after refueling and the fuel cap is not secured cor-rectly, the on–board diagnostic system will sense this asa system fault, turn on the MIL, and set DTC P0440.

Vehicle MarshalingThe transportation of new vehicles from the assemblyplant to the dealership can involve as many as 60 keycycles within 2 to 3 miles of driving. This type of operationcontributes to the fuel fouling of the spark plugs and willturn on the MIL with a set DTC P0300.

Poor Vehicle MaintenanceThe sensitivity of OBD II diagnostics will cause the MIL toturn on if the vehicle is not maintained properly. Restrictedair filters, fuel filters, and crankcase deposits due to lackof oil changes or improper oil viscosity can trigger actualvehicle faults that were not previously monitored prior toOBD II. Poor vehicle maintenance can not be classified asa ”non–vehicle fault,” but with the sensitivity of OBD IIdiagnostics, vehicle maintenance schedules must bemore closely followed.

Severe VibrationThe Misfire diagnostic measures small changes in therotational speed of the crankshaft. Severe driveline vibra-tions in the vehicle, such as caused by an excessiveamount of mud on the wheels, can have the same effecton crankshaft speed as misfire and, therefore, may setDTC P0300.

Related System FaultsMany of the OBD II system diagnostics will not run if thepowertrain control module (PCM)/engine controlmodule(ECM) detects a fault on a related system or component.One example would be that if the PCM/ECM detected aMisfire fault, the diagnostics on the catalytic converterwould be suspended until the Misfire fault was repaired. Ifthe Misfire fault is severe enough, the catalytic convertercan be damaged due to overheating and will never set aCatalyst DTC until the Misfire fault is repaired and the Cat-alyst diagnostic is allowed to run to completion. If this hap-pens, the customer may have to make two trips to thedealership in order to repair the vehicle.

SERIAL DATA COMMUNICATIONS

Class II Serial Data CommunicationsGovernment regulations require that all vehicle manufac-turers establish a common communication system. Thisvehicle utilizes the ”Class II” communication system. Eachbit of information can have one of two lengths: long orshort. This allows vehicle wiring to be reduced by transmit-ting and receiving multiple signals over a single wire. Themessages carried on Class II data streams are also priori-tized. If two messages attempt to establish communica-tions on the data line at the same time, only the messagewith higher priority will continue. The device with the lowerpriority message must wait. Themost significant result ofthis regulation is that it provides scan tool manufacturerswith the capability to access data from any make or modelvehicle that is sold.

The data displayed on the other scan tool will appear thesame, with some exceptions. Some scan tools will only beable to display certain vehicle parameters as values thatare a coded representation of the true or actual value. Onthis vehicle the scan tool displays the actual values for ve-hicle parameters. It will not be necessary to perform anyconversions from coded values to actual values.

ENGINE CONTROLS 1F – 411

DAEWOO V–121 BL4

ON–BOARD DIAGNOSTIC (OBD II)

On–Board Diagnostic TestsA diagnostic test is a series of steps, the result of which isa pass or fail reported to the diagnostic executive. Whena diagnostic test reports a pass result, the diagnosticexecutive records the following data:

The diagnostic test has been completed since thelast ignition cycle.

The diagnostic test has passed during the currentignition cycle.

The fault identified by the diagnostic test is not cur-rently active.

When a diagnostic test reports a fail result, the diagnosticexecutive records the following data:

The diagnostic test has been completed since thelast ignition cycle.

The fault identified by the diagnostic test is current-ly active.

The fault has been active during this ignition cycle. The operating conditions at the time of the failure.

Remember, a fuel trim Diagnostic Trouble Code (DTC)may be triggered by a list of vehicle faults. Make use of allinformation available (other DTCs stored, rich or lean con-dition, etc.) when diagnosing a fuel trim fault.

COMPREHENSIVE COMPONENTMONITOR DIAGNOSTIC OPERATIONComprehensive component monitoring diagnostics arerequired to monitor emissions–related input and outputpowertrain components.

Input ComponentsInput components are monitored for circuit continuity andout–of–range values. This includes rationality checking.Rationality checking refers to indicating a fault when thesignal from a sensor does not seem reasonable, i.e.Throttle Position (TP) sensor that indicates high throttleposition at low engine loads or Manifold Absolute Pressure(MAP) voltage. Input components may include, but are notlimited to, the following sensors:

Vehicle Speed Sensor (VSS). Crankshaft Position (CKP) sensor. Throttle Position (TP) sensor. Engine Coolant Temperature (ECT) sensor. Camshaft Position (CMP) sensor. Manifold Absolute Pressure (MAP) sensor.

In addition to the circuit continuity and rationality check,the ECT sensor is monitored for its ability to achieve asteady state temperature to enable closed loop fuel con-trol.

Output ComponentsOutput components are diagnosed for proper response tocontrol module commands. Components where functionalmonitoring is not feasible will be monitored for circuit conti-nuity and out–of–range values if applicable. Output com-ponents to be monitored include, but are not limited to thefollowing circuit:

Idle Air Control (IAC) Motor. Control module controlled EVAP Canister Purge

Valve. A/C relays. Cooling fan relay. VSS output. MIL control. Cruise control inhibit.

Refer to ”Powertrain Control Module/Engine Control Mod-ule” and Sensors in this section.

Passive and Active Diagnostic TestsA passive test is a diagnostic test which simply monitorsa vehicle system or component. Conversely, an activetest, actually takes some sort of action when performingdiagnostic functions, often in response to a failed passivetest. For example, the Exhaust Gas Recirculation (EGR)diagnostic active test will force the EGR valve open duringclosed throttle deceleration and/or force the EGR valveclosed during a steady state. Either action should result ina change in manifold pressure.

Intrusive Diagnostic TestsThis is any on–board test run by the Diagnostic Manage-ment System which may have an effect on vehicle perfor-mance or emission levels.

Warm–Up CycleA warm–up cycle means that engine temperature mustreach aminimum of 160³F (70³C) and rise at least 72³F(22³C) over the course of a trip.

Freeze FrameFreeze Frame is an element of the Diagnostic Manage-ment System which stores various vehicle information atthe moment an emissions–related fault is stored inmemory and when the Malfunction Indicator Lamp (MIL)is commanded on. These data can help to identify thecause of a fault.

Failure RecordsFailure Records data is an enhancement of the OBD IIFreeze Frame feature. Failure Records store the same ve-hicle information as does Freeze Frame, but it will storethat information for any fault which is stored in onboardmemory, while Freeze Frame stores information only foremission–related faults that command the MIL on.

1F – 412IENGINE CONTROLS

DAEWOO V–121 BL4

COMMON OBD II TERMS

DiagnosticWhen used as a noun, the word diagnostic refers to anyon–board test run by the vehicle’s Diagnostic Manage-ment System. A diagnostic is simply a test run on a systemor component to determine if the system or component isoperating according to specification. There are many diag-nostics, shown in the following list:

Misfire Oxygen Sensors (O2S) Heated Oxygen Sensor (HO2S) Exhaust Gas Recirculation (EGR) Catalyst monitoring

Enable CriteriaThe term ”enable criteria” is engineering language for theconditions necessary for a given diagnostic test to run.Each diagnostic has a specific list of conditions whichmust be met before the diagnostic will run.

”Enable criteria” is another way of saying ”conditions re-quired.”

The enable criteria for each diagnostic is listed on the firstpage of the Diagnostic Trouble Code (DTC) descriptionunder the heading ”Conditions for Setting the DTC.” En-able criteria varies with each diagnostic and typically in-cludes, but is not limited to, the following items:

Engine speed. Vehicle speed Engine Coolant Temperature (ECT) Manifold Absolute Pressure (MAP) Barometric Pressure (BARO) Intake Air Temperature (IAT) Throttle Position (TP) High canister purge Fuel trim A/C on

TripTechnically, a trip is a key–on run key–off cycle in which allthe enable criteria for a given diagnostic are met, allowingthe diagnostic to run. Unfortunately, this concept is notquite that simple. A trip is official when all the enable crite-ria for a given diagnostic are met. But because the enablecriteria vary from one diagnostic to another, the definitionof trip varies as well. Some diagnostics are run when thevehicle is at operating temperature, some when the ve-hicle first starts up; some require that the vehicle be cruis-ing at a steady highway speed, some run only when thevehicle is at idle; some diagnostics function with theTorque Converter Clutch (TCC) disabled. Some run onlyimmediately following a cold engine startup.

A trip then, is defined as a key–on run key–off cycle inwhich the vehicle was operated in such a way as to satisfythe enables criteria for a given diagnostic, and this diag-nostic will consider this cycle to be one trip. However,

another diagnostic with a different set of enable criteria(which were not met) during this driving event, would notconsider it a trip. No trip will occur for that particular diag-nostic until the vehicle is driven in such a way as to meetall the enable criteria

Diagnostic InformationThe diagnostic charts and functional checks are designedto locate a faulty circuit or component through a processof logical decisions. The charts are prepared with the re-quirement that the vehicle functioned correctly at the timeof assembly and that there are not multiple faults present.

There is a continuous self–diagnosis on certain controlfunctions. This diagnostic capability is complimented bythe diagnostic procedures contained in this manual. Thelanguage of communicating the source of the malfunctionis a system of diagnostic trouble codes. When a malfunc-tion is detected by the control module, a diagnostic troublecode is set and the Malfunction Indicator Lamp (MIL) is illu-minated.

Malfunction Indicator Lamp (MIL)The Malfunction Indicator Lamp (MIL) is required by On–Board Diagnostics (OBD II) that it illuminates under a strictset of guide lines.

Basically, the MIL is turned on when the powertrain controlmodule (PCM)/engine control module (ECM) detects aDTC that will impact the vehicle emissions.

The MIL is under the control of the Diagnostic Executive.The MIL will be turned on if an emissions–related diagnos-tic test indicates a malfunction has occurred. It will stay onuntil the system or component passes the same test, forthree consecutive trips, with no emissions related faults.

Extinguishing the MILWhen the MIL is on, the Diagnostic Executive will turn offthe MIL after three consecutive trips that a ”test passed”has been reported for the diagnostic test that originallycaused the MIL to illuminate. Although the MIL has beenturned off, the DTC will remain in the PCM/ECM memory(both Freeze Frame and Failure Records) until forty (40)warm–up cycles after no faults have been completed.

If the MIL was set by either a fuel trim or misfire–relatedDTC, additional requirements must be met. In addition tothe requirements stated in the previous paragraph, theserequirements are as follows:

The diagnostic tests that are passed must occurwith 375 rpm of the rpm data stored at the time thelast test failed.

Plus or minus ten percent of the engine load thatwas stored at the time the last test failed. Similarengine temperature conditions (warmed up orwarming up) as those stored at the time the lasttest failed.

Meeting these requirements ensures that the fault whichturned on the MIL has been corrected.

The MIL is on the instrument panel and has the followingfunctions:

ENGINE CONTROLS 1F – 413

DAEWOO V–121 BL4

It informs the driver that a fault that affects vehicleemission levels has occurred and that the vehicleshould be taken for service as soon as possible.

As a system check, the MIL will come on with thekey ON and the engine not running. When the en-gine is started, the MIL will turn OFF.

When the MIL remains ON while the engine is run-ning, or when a malfunction is suspected due to adriveability or emissions problem, an OBD II Sys-tem Check must be performed. The procedures forthese checks are given in OBD II System Check.These checks will expose faults which may not bedetected if other diagnostics are performed first.

Data Link Connector (DLC)The provision for communicating with the control moduleis the Data Link Connector (DLC). The DLC is used to con-nect to a scan tool. Some common uses of the scan toolare listed below:

Identifying stored DTCs. Clearing DTCs. Performing output control tests. Reading serial data.

DTC TYPESEach Diagnostic Trouble Code (DTC) is directly related toa diagnostic test. The Diagnostic Management Systemsets DTC based on the failure of the tests during a trip ortrips. Certain tests must fail two consecutive trips beforethe DTC is set. The following are the three types of DTCsand the characteristics of those codes:

Type A Emissions related. Requests illumination of the Malfunction Indicator

Lamp (MIL) of the first trip with a fail. Stores a History DTC on the first trip with a fail. Stores a Freeze Frame (if empty). Stores a Fail Record. Updates the Fail Record each time the diagnostic

test fails.

Type B Emissions related. ”Armed” after one trip with a fail. ”Disarmed” after one trip with a pass. Requests illumination of the MIL on the second

consecutive trip with a fail. Stores a History DTC on the second consecutive

trip with a fail (The DTC will be armed after the firstfail).

Stores a Freeze Frame on the second consecutivetrip with a fail (if empty).

Store Fail Record when the first test fails (not de-pendent on consecutive trip fails).

Updates the Fail Record each time the diagnostictest fails.

Type D(Type D non–emissions related are not utilized on certainvehicle applications).

Non–Emissions related. Does not request illumination of any lamp. Stores a History DTC on the first trip with a fail. Does not store a Freeze Frame. Stores Fail Record when test fails. Updates the Fail Record each time the diagnostic

test fails.

Important : Only four Fail Records can be stored. EachFail Record is for a different DTC. It is possible that therewill not be Fail Records for every DTC if multiple DTCs areset.

Special Cases of Type B Diagnostic TestsUnique to the misfire diagnostic, the Diagnostic Executivehas the capability of alerting the vehicle operator to poten-tially damaging levels of misfire. If a misfire condition ex-ists that could potentially damage the catalytic converteras a result of high misfire levels, the Diagnostic Executivewill command the MIL to flash at a rate of once per secondduring those the time that the catalyst damaging misfirecondition is present.

Fuel trim and misfire are special cases of Type B diagnos-tics. Each time a fuel trim or misfire malfunction is de-tected, engine load, engine speed, and engine coolanttemperature (ECT) are recorded.

When the ignition is turned off, the last reported set of con-ditions remain stored. During subsequent ignition cycles,the stored conditions are used as a reference for similarconditions. If a malfunction occurs during two consecutivetrips, the Diagnostic Executive treats the failure as a nor-mal Type B diagnostic, and does not use the stored condi-tions. However, if a malfunction occurs on two non–con-secutive trips, the stored conditions are compared with thecurrent conditions. The MIL will then illuminate under thefollowing conditions:

When the engine load conditions are within 10% ofthe previous test that failed.

Engine speed is within 375 rpm of the previous testthat failed.

ECT is in the same range as the previous test thatfailed.

READING DIAGNOSTIC TROUBLECODESThe procedure for reading diagnostic trouble code(s) is touse a diagnostic scan tool. When reading DiagnosticTrouble Codes (DTCs), follow the instructions supplied bytool manufacturer.

Clearing Diagnostic Trouble CodesImportant : Do not clear DTCs unless directed to do soby the service information provided for each diagnosticprocedure. When DTCs are cleared, the Freeze Frame

1F – 414IENGINE CONTROLS

DAEWOO V–121 BL4

and Failure Record data which may help diagnose an in-termittent fault will also be erased from memory. If the faultthat caused the DTC to be stored into memory has beencorrected, the Diagnostic Executive will begin to count the”warm–up” cycles with no further faults detected, the DTCwill automatically be cleared from the powertrain controlmodule (PCM)/engine control module (ECM) memory.

To clear DTCs, use the diagnostic scan tool. When a scantool is not available, DTCs can also be cleared by discon-necting one of the following sources for at least thirty (30)seconds:

Notice : To prevent system damage, the ignition key mustbe OFF when disconnecting or reconnecting battery pow-er.

The power source to the control module. Examples:fuse, pigtail at battery PCM/ECM connectors etc.

The negative battery cable. (Disconnecting the neg-ative battery cable will result in the loss of otheronboard memory data, such as preset radio tun-ing).

DTC ModesOn On–Board Diagnostic (OBD II) passenger cars thereare five options available in the scan tool DTC mode to dis-play the enhanced information available. A description ofthe new modes, DTC Info and Specific DTC, follows. Afterselecting DTC, the following menu appears:

DTC Info. Specific DTC. Freeze Frame. Fail Records (not all applications). Clear Info.

The following is a brief description of each of the sub me-nus in DTC Info and Specific DTC. The order in which theyappear here is alphabetical and not necessarily the waythey will appear on the scan tool.

DTC Information ModeUse the DTC info mode to search for a specific type ofstored DTC information. There are seven choices. Theservice manual may instruct the technician to test forDTCs in a certain manner. Always follow published serviceprocedures.

To get a complete description of any status, press the ”En-ter” key before pressing the desired F–key. For example,pressing ”Enter” then an F–key will display a definition ofthe abbreviated scan tool status.

DTC StatusThis selection will display any DTCs that have not run dur-ing the current ignition cycle or have reported a test failureduring this ignition up to a maximum of 33 DTCs. DTCtests which run and pass will cause that DTC number tobe removed from the scan tool screen.

Fail This Ign. (Fail This Ignition)This selection will display all DTCs that have failed duringthe present ignition cycle.

HistoryThis selection will display only DTCs that are stored in thePCM/ECM’s history memory. It will not display type BDTCs that have not requested the Malfunction IndicatorLamp (MIL). It will display all type A and B DTCs that haverequested the MIL and have failed within the last 40 warm–up cycles. In addition, it will display all type C and type DDTCs that have failed within the last 40 warm–up cycles.

Last Test FailThis selection will display only DTCs that failed the lasttime the test ran. The last test may have run during a pre-vious ignition cycle if a type A or type B DTC is displayed.For type C and type D DTCs, the last failure must have oc-curred during the current ignition cycle to appear as LastTest Fail.

MIL RequestThis selection will display only DTCs that are requestingthe MIL. Type C and type D DTCs cannot be displayed us-ing this option. This selection will report type B DTCs onlyafter the MIL has been requested.

Not Run SCC (Not Run Since Code Clear)This option will display up to 33 DTCs that have not runsince the DTCs were last cleared. Since any displayedDTCs have not run, their condition (passing or failing) isunknown.

Test Fail SCC (Test Failed Since CodeClear)This selection will display all active and history DTCs thathave reported a test failure since the last time DTCs werecleared. DTCs that last failed more than 40 warm–upcycles before this option is selected will not be displayed.

Specific DTC ModeThis mode is used to check the status of individual diag-nostic tests by DTC number. This selection can be ac-cessed if a DTC has passed, failed or both. Many OBD IIDTC mode descriptions are possible because of the ex-tensive amount of information that the diagnostic execu-tive monitors regarding each test. Some of the many pos-sible descriptions follow with a brief explanation.

The ”F2” key is used, in this mode, to display a descriptionof the DTC. The ”Yes” and ”No” keys may also be used todisplay more DTC status information. This selection willonly allow entry of DTC numbers that are supported by thevehicle being tested. If an attempt is made to enter DTCnumbers for tests which the diagnostic executive does notrecognize, the requested information will not be displayedcorrectly and the scan tool may display an error message.The same applies to using the DTC trigger option in theSnapshot mode. If an invalid DTC is entered, the scan toolwill not trigger.

ENGINE CONTROLS 1F – 415

DAEWOO V–121 BL4

Failed Last TestThis message display indicates that the last diagnostictest failed for the selected DTC. For type A and type BDTCs, this message will be displayed during subsequentignition cycles until the test passes or DTCs are cleared.For type C and type D DTCs, this message will clear whenthe ignition is cycled.

Failed Since ClearThis message display indicates that the DTC has failed atleast once within the last 40 warm–up cycles since the lasttime DTCs were cleared.

Failed This Ig. (Failed This Ignition)This message display indicates that the diagnostic testhas failed at least once during the current ignition cycle.This message will clear when DTCs are cleared or the igni-tion is cycled.

History DTCThis message display indicates that the DTC has beenstored in memory as a valid fault. A DTC displayed as aHistory fault may not mean that the fault is no longer pres-ent. The history description means that all the conditionsnecessary for reporting a fault have been met (maybeeven currently), and the information was stored in the con-trol module memory.

MIL RequestedThis message display indicates that the DTC is currentlycausing the MIL to be turned ON. Remember that onlytype A and type B DTCs can request the MIL. The MIL re-quest cannot be used to determine if the DTC fault condi-tions are currently being experienced. This is because thediagnostic executive will require up to three trips duringwhich the diagnostic test passes to turn OFF the MIL.

Not Run Since CI (Not Run Since Cleared)This message display indicates that the selected diagnos-tic test has not run since the last time DTCs were cleared.Therefore, the diagnostic test status (passing or failing) isunknown. After DTCs are cleared, this message will con-tinue to be displayed until the diagnostic test runs.

Not Run This Ig. (Not Run This Ignition)This message display indicates that the selected diagnos-tic test has not run during this ignition cycle.

Test Ran and PassedThis message display indicates that the selected diagnos-tic test has done the following:

Passed the last test. Run and passed during this ignition cycle. Run and passed since DTCs were last cleared.

If the indicated status of the vehicle is ”Test Ran andPassed” after a repair verification, the vehicle is ready tobe released to the customer.

If the indicated status of the vehicle is ”Failed This Ignition”after a repair verification, then the repair is incomplete andfurther diagnosis is required.

Prior to repairing a vehicle, status information can be usedto evaluate the state of the diagnostic test, and to helpidentify an intermittent problem. The technician can con-clude that although the MIL is illuminated, the fault condi-tion that caused the code to set is not present. An intermit-tent condition must be the cause.

PRIMARY SYSTEM–BASEDDIAGNOSTICSThere are primary system–based diagnostics which eval-uate system operation and its effect on vehicle emissions.The primary system–based diagnostics are listed belowwith a brief description of the diagnostic function:

Oxygen Sensor DiagnosisThe fuel control Oxygen Sensor (O2S) is diagnosed forthe following conditions:

Slow response. Response time (time to switch R/L or L/R). Inactive signal (output steady at bias voltage

approx. 450 mv). Signal fixed high. Signal fixed low.

The catalyst monitor Heated Oxygen Sensor (HO2S) isdiagnosed for the following conditions:

Heater performance (time to activity on cold start). Signal fixed low during steady state conditions or

power enrichment (hard acceleration when a rich-mixture should be indicated).

Signal fixed high during steady state conditions ordeceleration mode (deceleration when a lean mix-ture should be indicated).

Inactive sensor (output steady at approximately 438mv).

If the oxygen sensor pigtail wiring, connector or terminalare damaged, the entire oxygen sensor assembly must bereplaced. Do not attempt to repair the wiring, connector orterminals. In order for the sensor to function properly, itmust have clean reference air provided to it. This clean airreference is obtained by way of the oxygen sensor wire(s).Any attempt to repair the wires, connector or terminalscould result in the obstruction of the reference air and de-grade oxygen sensor performance.

Misfire Monitor Diagnostic OperationThe misfire monitor diagnostic is based on crankshaftrotational velocity (reference period) variations. The pow-ertrain control module (PCM)/engine controlmodule(ECM) determines crankshaft rotational velocity using theCrankshaft Position (CKP) sensor and the Camshaft Posi-tion (CMP) sensor. When a cylinder misfires, the crank-shaft slows down momentarily. By monitoring the CKP andCMP sensor signals, the PCM/ECM can calculate whena misfire occurs.

1F – 416IENGINE CONTROLS

DAEWOO V–121 BL4

For a non–catalyst damaging misfire, the diagnostic will berequired to monitor a misfire present for between1000–3200 engine revolutions.

For catalyst–damaging misfire, the diagnostic will respondto misfire within 200 engine revolutions.

Rough roads may cause false misfire detection. A roughroad will cause torque to be applied to the drive wheels anddrive train. This torque can intermittently decrease thecrankshaft rotational velocity. This may be falsely de-tected as a misfire.

A rough road sensor, or G sensor, works together with themisfire detection system. The G sensor produces a volt-age that varies along with the intensity of road vibrations.When the PCM/ECM detects a rough road, the misfiredetection system is temporarily disabled.

Misfire CountersWhenever a cylinder misfires, the misfire diagnosticcounts the misfire and notes the crankshaft position at thetime the misfire occurred. These ”misfire counters” are ba-sically a file on each engine cylinder. A current and a histo-ry misfire counter are maintained for each cylinder. Themisfire current counters (Misfire Cur #1–4) indicate thenumber of firing events out of the last 200 cylinder firingevents which were misfires. The misfire current counterwill display real time data without a misfire DiagnosticTrouble Code (DTC) stored. The misfire history counters(Misfire Hist #1–4) indicate the total number of cylinder fir-ing events which were misfires. The misfire history count-ers will display 0 until the misfire iagnostic has failed anda DTC P0300 is set. Once the misfire DTC P0300 is set,the misfire history counters will be updated every 200 cyl-inder firing events. A misfire counter is maintained for eachcylinder.

If the misfire diagnostic reports a failure, the diagnosticexecutive reviews all of the misfire counters before report-ing a DTC. This way, the diagnostic executive reports themost current information.

When crankshaft rotation is erratic, a misfire condition willbe detected. Because of this erratic condition, the datathat is collected by the diagnostic can sometimes incor-rectly identify which cylinder is misfiring.

Use diagnostic equipment to monitor misfire counter dataon On–Board Diagnostic (OBD II) compliant vehicles.Knowing which specific cylinder(s) misfired can lead to theroot cause, even when dealing with amultiple cylinder mis-fire. Using the information in the misfire counters, identifywhich cylinders are misfiring. If the counters indicate cylin-ders numbers 1 and 4 misfired, look for a circuit or compo-nent common to both cylinders number 1 and 4.

The misfire diagnostic may indicate a fault due to a tempo-rary fault not necessarily caused by a vehicle emissionsystem malfunction. Examples include the followingitems:

Contaminated fuel. Low fuel. Fuel–fouled spark plugs. Basic engine fault.

Fuel Trim System Monitor DiagnosticOperationThis system monitors the averages of short–term andlong–term fuel trim values. If these fuel trim values stay attheir limits for a calibrated period of time, a malfunction isindicated. The fuel trim diagnostic compares the averagesof short–term fuel trim values and long–term fuel trim val-ues to rich and lean thresholds. If either value is within thethresholds, a pass is recorded. If both values are outsidetheir thresholds, a rich or lean DTC will be recorded.

The fuel trim system diagnostic also conducts an intrusivetest. This test determines if a rich condition is beingcaused by excessive fuel vapor from the Evaporative(EVAP) Emission canister. In order to meet OBD II re-quirements, the control module uses weighted fuel trimcells to determine the need to set a fuel trim DTC. A fueltrim DTC can only be set if fuel trim counts in the weightedfuel trim cells exceed specifications. This means that thevehicle could have a fuel trim problem which is causing aproblem under certain conditions (i.e., engine idle high dueto a small vacuum leak or rough idle due to a large vacuumleak) while it operates fine at other times. No fuel trim DTCwould set (although an engine idle speed DTC or HO2SDTC may set). Use a scan tool to observe fuel trim countswhile the problem is occurring.

A fuel trim DTC may be triggered by a number of vehiclefaults. Make use of all information available (other DTCsstored, rich or lean condition, etc.) when diagnosing a fueltrim fault.

Fuel Trim Cell Diagnostic WeightsNo fuel trim DTC will set regardless of the fuel trim countsin cell 0 unless the fuel trim counts in the weighted cells arealso outside specifications. This means that the vehiclecould have a fuel trim problem which is causing a problemunder certain conditions (i.e. engine idle high due to asmall vacuum leak or rough due to a large vacuum leak)while it operates fine at other times. No fuel trim DTCwould set (although an engine idle speed DTC or HO2SDTC may set). Use a scan tool to observe fuel trim countswhile the problem is occurring.

SECTION : 1G

ENGINE EXHAUST

TABLE OF CONTENTSSPECIFICATIONS 1G–1. . . . . . . . . . . . . . . . . . . . . . . . . .

FASTENER TIGHTENING SPECIFICATIONS 1G–1.

COMPONENT LOCATOR 1G–2. . . . . . . . . . . . . . . . . . . .

EXHAUST SYSTEM 1G–2. . . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE AND REPAIR 1G–3. . . . . . . . . . . . . . .

ON–VEHICLE SERVICE 1G–3. . . . . . . . . . . . . . . . . . . . .

MAIN CATALYTIC CONVERTER ANDCONNECTING PIPE 1G–3. . . . . . . . . . . . . . . . . . . . .

AUXILIARY CATALYTIC CONVERTER 1G–5. . . . . . .

MUFFLER – FRONT 1G–7. . . . . . . . . . . . . . . . . . . . . . .

MUFFLER – REAR 1G–9. . . . . . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 1G–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

EXHAUST SYSTEM 1G–12. . . . . . . . . . . . . . . . . . . . . .

MUFFLER 1G–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CATALYTIC CONVERTERS 1G–12. . . . . . . . . . . . . . .

SPECIFICATIONS

FASTENER TIGHTENING SPECIFICATIONS

Application Nm Lb–Ft Lb–In

Auxiliary Catalytic Converter–to–Exhaust Manifold Nuts 40 30 –

Catalytic Converter–to–Front Muffler Pipe 30 22 –

Exhaust Manifold Cover Bolts 15 11 –

Front Connecting Pipe–to–Auxiliary Catalytic Converter Nuts 40 30 –

Front Muffler Pipe–to–Catalytic Converter Nuts 30 22 –

Front Muffler Pipe–to–Rear Muffler Pipe Holding Clamp Nut 50 37 –

Post–Converter Oxygen Sensor Electrical Connector 41 30 –

1G – 2IENGINE EXHAUST

DAEWOO V–121 BL4

COMPONENT LOCATOR

EXHAUST SYSTEM

1. Trim Ring (if equipped)2. Muffler3. Metal Clamp4. Front Muffler

5. Catalytic Converter6. Post–Converter Heated Oxygen Sensor7. Auxiliary Catalytic Converter

ENGINE EXHAUST 1G – 3

DAEWOO V–121 BL4

MAINTENANCE AND REPAIR

ON–VEHICLE SERVICE

MAIN CATALYTIC CONVERTER ANDCONNECTING PIPE

Removal Procedure

1. Remove the post–converter heated oxygen sensor.

2. Remove the connecting pipe nuts and the gasketfrom the auxiliary catalytic converter.

3. Remove the catalytic converter nuts and the gasketfrom the front muffler.

4. Disconnect the main catalytic converter and theconnecting pipe from the rubber hanger.

1G – 4IENGINE EXHAUST

DAEWOO V–121 BL4

Installation Procedure

1. Install the catalytic converter and the gasket to thefront muffler. Use the nuts to secure the converter.

TightenTighten the catalytic converter–to–front muffler pipenuts to 30 Nm (22 lb–ft).

2. Connect the main catalytic converter and the con-necting pipe to the rubber hanger.

3. Install the gasket and the connecting pipe nuts tothe auxiliary catalytic converter.

TightenTighten the front connecting pipe–to–auxiliary cata-lytic converter nuts to 35 Nm (26 lb–ft).

4. Install the post–converter heated oxygen sensor.

TightenTighten the post–converter heated oxygen sensor to41 Nm (30 lb–ft).

ENGINE EXHAUST 1G – 5

DAEWOO V–121 BL4

AUXILIARY CATALYTIC CONVERTER

Removal Procedure

1. Disconnect the pre–converter oxygen sensor elec-trical connector.

2. Remove the exhaust manifold cover bolts and theexhaust manifold cover.

3. Remove the auxiliary catalytic converter upperflange nuts.

1G – 6IENGINE EXHAUST

DAEWOO V–121 BL4

4. Remove the auxiliary catalytic converter lowerflange nuts.

5. Remove the auxiliary catalytic converter and thegaskets.

Installation Procedure

1. Install the auxiliary catalytic converter and the gas-kets.

Important : Position the auxiliary catalytic converter ontothe exhaust manifold flange with one upper flange nut andbolt.2. Install the auxiliary catalytic converter lower flange

nuts and the bolts.

TightenTighten the front connecting pipe–to–auxiliary cata-lytic converter nuts to 35 Nm (26 lb–ft).

3. Install the remaining auxiliary catalytic converterupper flange nuts.

TightenTighten the auxiliary catalytic converter–to–exhaustmanifold nuts to 35 Nm (26 lb–ft).

ENGINE EXHAUST 1G – 7

DAEWOO V–121 BL4

4. Install the exhaust manifold cover and the exhaustmanifold cover bolts.

TightenTighten the exhaust manifold cover bolts to 15 Nm(11 lb–ft).

5. Connect the pre–converter oxygen sensor electricalconnector.

MUFFLER – FRONT

Removal Procedure

1. Remove the nuts and the gasket that secure thefront muffler pipe to the catalytic converter flange.

1G – 8IENGINE EXHAUST

DAEWOO V–121 BL4

2. Detach the front muffler assembly from the frontrubber hangers.

3. Loosen the front muffler pipe–to–rear muffler pipeholding clamp nut and the washer.

4. Disconnect the front muffler pipe from the rear rub-ber hanger.

5. Remove the front muffler pipe.6. Check the exhaust pipe and the front muffler pipe

for holes, damage, open seams, or other deteriora-tion which could permit exhaust fumes to seep intothe passenger compartment or the trunk.

Installation Procedure

1. Secure the front muffler pipe to the rear rubberhanger near the rear muffler pipe holding clamp.

2. Place the front muffler pipe into the rear mufflerpipe.

3. Secure the front muffler pipe to the rear mufflerpipe with the holding clamp, the washer, and thenut.

TightenTighten the front muffler pipe–to–rear muffler pipeholding clamp nut to 50 Nm (37 lb–ft).

ENGINE EXHAUST 1G – 9

DAEWOO V–121 BL4

4. Attach the front muffler assembly to the front rubberhangers. Loosely secure the front muffler assemblyto the catalytic converter flange.

5. Secure the front muffler assembly to the catalyticconverter with the nuts.

TightenTighten the front muffler pipe–to–catalytic converternuts to 35 Nm (26 lb–ft).

MUFFLER – REAR

Removal Procedure

1. Loosen the front muffler pipe–to–rear muffler pipeholding clamp nut and the washer.

2. Spread the loosened holding clamp and position itaway from the junction of the front muffler pipe andthe rear muffler pipe.

3. Separate the rear muffler pipe from the front mufflerpipe.

1G – 10IENGINE EXHAUST

DAEWOO V–121 BL4

4. Remove the bolt that secures the trim ring, (ifequipped), to the rear muffler pipe.

5. Remove the trim ring.6. Detach the rear muffler pipe from the rear rubber

hangers at the top of the rear muffler assemblynear the exhaust tail pipe and near the junction ofthe rear muffler pipe with the front muffler pipe.

7. Remove the rear muffler assembly.8. Check the rear muffler and the pipes for holes,

damage, open seams, and other deteriorationwhich could permit exhaust fumes to seep into thepassenger compartment or the trunk.

Installation Procedure

1. Place the exhaust tail pipe trim ring, (if equipped),on the rear muffler pipe.

2. Secure the exhaust pipe trim ring on the rear muf-fler pipe, and tighten the exhaust trim ring bolt untilit bottoms out on the exhaust pipe. Tighten an addi-tional quarter turn.

3. Secure the rear muffler assembly to the rear rubberhangers near the exhaust tail pipe and near thejunction of the rear muffler pipe with the front muf-fler pipe.

ENGINE EXHAUST 1G – 11

DAEWOO V–121 BL4

4. Place the rear muffler pipe into the front mufflerpipe.

5. Secure the rear muffler pipe to the front mufflerpipe with the holding clamp, the washer, and thenut.

TightenTighten the front muffler pipe–to–rear muffler pipeholding clamp nut to 70 Nm (52 lb–ft).

1G – 12IENGINE EXHAUST

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

EXHAUST SYSTEMNotice : When you are inspecting or replacing exhaustsystem components, make sure there is adequate clear-ance from all points on the underbody to avoid possibleoverheating of the floor pan and possible damage to thepassenger compartment insulation and trim materials.

CAUTION : Check the complete exhaust system, thenearby body areas, and the trunk lid for broken, dam-aged, missing or mispositioned parts, open seams,holes, loose connections or other deteriorationwhich could permit exhaust fumes to seep into thetrunk or passenger compartment. Dust or water in thetrunk may be an indication of a problem in one ofthese areas. Any defects should be corrected immedi-ately.

MUFFLERAside from the exhaust manifold connection and the rearmuffler–to–front muffler joint, the exhaust system uses aflange and seal joint design. The exhaust manifold– to–ex-haust pipe connection is of the flex joint type.If holes, open

seams or any deterioration is discovered upon inspectionof the front muffler and pipe assembly, the complete as-sembly should be replaced. The same procedure is appli-cable to the rear muffler assembly.

Heat shields in the front and the rear muffler assemblypositions as well as in the catalytic converter, protect thevehicle and the environment from high temperatures de-veloped from the exhaust system.

CATALYTIC CONVERTERSNotice : When jacking or lifting the vehicle from the bodyside rails, be certain the lift pads do not contact the catalyt-ic converter, as this could damage the catalytic converter.

Notice : The catalytic converter requires the use of un-leaded fuel only, or damage to the catalyst will result.

The catalytic converter is an emission control device add-ed to the exhaust system to reduce pollutants escapingfrom the exhaust pipes.

The oxidation catalyst is coated with a catalytic materialcontaining platinum and palladium, which reduces levelsof hydrocarbon (HC) and carbon monoxide (CO) from theexhaust gas. The three–way catalyst has coatings whichcontain platinum and rhodium, which additionally lower thelevels of oxides of nitrogen (NOx).

SECTION 3

WIRING DIAGRAM FOR POWER SUPPLIES

3–2WWIRING DIAGRAM FOR POWER SUPPLIES

1. IGNITION SWITCH CIRCUIT

WIRING DIAGRAM FOR POWER SUPPLIESW3–3

2. 30 Ter BAT+ POWER SUPPLY CIRCUIT(PASSENGER ROOM FUSE BOX)

3–4WWIRING DIAGRAM FOR POWER SUPPLIES

3. 15A IGN 2, 15C ACC POWER SUPPLY CIRCUIT(PASSENGER ROOMFUSE BOX)

WIRING DIAGRAM FOR POWER SUPPLIESW3–5

4. ENGINE ROOM FUSE & RELAY CIRCUIT

3–6WWIRING DIAGRAM FOR POWER SUPPLIES

WIRING DIAGRAM FOR POWER SUPPLIESW3–7

SECTION : 3A

AUTOMATIC TRANSAXLE DRIVE AXLE

TABLE OF CONTENTSSPECIFICATIONS 3A–1. . . . . . . . . . . . . . . . . . . . . . . . . .

FASTENER TIGHTENING SPECIFICATIONS 3A–1. . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS 3A–2. . . . . . . . . . . . . . . . . . . . . . . . . . .

SPECIAL TOOLS TABLE 3A–2. . . . . . . . . . . . . . . . . . .

COMPONENT LOCATOR 3A–2. . . . . . . . . . . . . . . . . . . .

FRONT DRIVE AXLE 3A–2. . . . . . . . . . . . . . . . . . . . . .

MAINTENANCE AND REPAIR 3A–4. . . . . . . . . . . . . . .

ON–VEHICLE SERVICE 3A–4. . . . . . . . . . . . . . . . . . . . .

DRIVE AXLE ASSEMBLY 3A–4. . . . . . . . . . . . . . . . . .

UNIT REPAIR 3A–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OUTER JOINT SEAL 3A–8. . . . . . . . . . . . . . . . . . . . . .

INNER TRIPOT SEAL 3A–9. . . . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 3A–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FRONT DRIVE AXLE 3A–13. . . . . . . . . . . . . . . . . . . . .

SPECIFICATIONS

FASTENER TIGHTENING SPECIFICATIONS

Application N·m Lb–Ft Lb–In

Axle Shaft Caulking Nut Initial Torque 180 134 –

Axle Shaft Caulking Nut Final Torque 50 + 60³ 37 + 60³ –

Lower Ball Joint Nut and Bolt 60 44 –

Tie Rod Nut 60 44 –

Wheel Nuts (Steel Wheel) 90 66 –

3A – 2IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

SPECIAL TOOLS

SPECIAL TOOLS TABLE

J–8059Snap Ring Pliers

KM–507–BBall Joint Separator

KM–460–AAxle Shaft Remover

J–35566Seal Clamp Pliers

COMPONENT LOCATOR

FRONT DRIVE AXLE

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 3

DAEWOO V–121 BL4

1. Caulking Nut2. C/V Joint3. Snap Ring4. Axle Shaft (right–hand shown, left–hand similar)5. Seal Retaining Clamp6. Drive Axle Outboard Seal7. Seal Retaining Clamp

8. Seal Retaining Clamp9. Drive Axle Inboard Seal10. Seal Retaining Clamp11. Tripot Joint Retaining Ring12. Tripot Joint13. Shaft Retaining Ring14. Tripot Housing

3A – 4IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

MAINTENANCE AND REPAIR

ON–VEHICLE SERVICE

DRIVE AXLE ASSEMBLYTools Required

KM–507–B Ball Joint SeparatorKM–460–A Axle Shaft Remover

Removal Procedure

1. Raise and suitably support the vehicle.2. Remove the wheels. Refer toSection 2E, Tires and

Wheels.3. Remove the engine under covers. Refer toSection

9N, Frame and Underbody.4. Remove the axle shaft caulking nut. Discard the

nut.5. Remove the lower ball joint nut and bolt.

Notice : Use only the recommended tool for separatingthe lower ball joint. Failure to use the recommended toolmay cause damage to the ball joint and the seal.6. Separate the steering knuckle from the lower ball

joint using the ball joint separator KM–507–B.

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 5

DAEWOO V–121 BL4

7. Remove the tie rod nut.

Notice : Use only the recommended tool for separatingthe tie rod from the knuckle/strut assembly. Failure to usethe recommended tool may cause damage to the knuckle/strut assembly.8. Separate the tie rod end using the ball joint separa-

tor KM–507–B.

9. Push the drive axle shaft from the wheel hub.Important : Support the unfastened end of the drive axle.Do not allow the drive axle to dangle freely from the trans-axle for any length of time after it has been removed fromthe wheel hub.

Important : Place a drain pan below the transaxle to catchthe escaping fluid. Cap the transaxle drive opening afterthe drive axle has been removed to keep the fluid in andany contamination out.10. Remove the drive axle from the transaxle using the

axle shaft remover KM–460–A.

3A – 6IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

Installation Procedure

Notice : Do not damage the seals.1. Clean the hub seal and the transaxle seal.2. Install the drive axle into the transaxle.3. Install the wheel hub onto the axle shaft.

4. Mount the steering knuckle onto the lower ball joint.

5. Install the tie rod into the knuckle/strut and installthe tie rod nut.

TightenTighten the tie rod nut to 60 Nm (44 lb–ft).

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 7

DAEWOO V–121 BL4

6. Install the lower ball joint bolt and nut.

TightenTighten the lower ball joint bolt and nut to 60 N·m (44lb–ft).

7. Loosely install a new axle shaft caulking nut. Al-ways use a new nut.

8. Install the wheels. Loosely install the bolts. RefertoSection 2E, Tires and Wheels.

9. Lower the vehicle to the floor.

TightenTighten the wheel bolts to 90 N·m (66 lb–ft).

10. Tighten the axle shaft caulking nut to 180 N·m (134lb–ft). Loosen the nut and re–tighten the nut to 50N·m (37 lb–ft). Then tighten the nut further by 60degrees.

11. Peen the caulking nut with a punch and a hammeruntil the nut is locked into place on the axle shafthub.

12. Install the engine under covers. Refer toSection 9N,Frame and Underbody.

13. Refill the transaxle fluid to the proper level. RefertoSection 5A, 4T40E Automatic Transaxle.

3A – 8IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

UNIT REPAIR

OUTER JOINT SEALTools RequiredJ–8059 Snap Ring Pliers

Removal Procedure

1. Remove the drive axle from the vehicle. Referto”Drive Axle Assembly” in this section.

2. Remove the large seal retaining clamp. Discard theclamp.

3. Remove the small seal retaining clamp. Discard theclamp.

4. Degrease the joint.5. Spread the snap ring using the snap ring pliers

J–8059 and remove the outer joint from the axleshaft.

CAUTION : Do not disassemble the outer joint assem-bly. Parts are match fit and cannot be serviced sepa-rately. Improper reassembly will adversely affect bothperformance and safety.6. Remove the seal from the joint assembly.

Installation Procedure

Tools RequiredJ–35566 Seal Clamp Pliers1. Install the seal onto the axle shaft.2. Spread the snap ring using the snap ring pliers

J–8059 and install the outer joint onto the axleshaft.

3. Fill the joint seal with 175 to 195 g (6.2 to 6.9ounces) of the recommended grease. Repack thejoint with 175 to 195 g (6.2 to 6.9 ounces) of therecommended grease.

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 9

DAEWOO V–121 BL4

4. Install a new large seal retaining clamp and a newsmall seal retaining clamp.

5. Crimp the new small seal retaining clamp and thenew large seal retaining clamp using the seal clamppliers J–35566.

6. Install the drive axle shaft to the vehicle. Referto”Drive Axle Assembly” in this section.

INNER TRIPOT SEALTools RequiredJ–8059 Snap Ring Pliers

Removal Procedure

1. Remove the drive axle from the vehicle. Referto”Drive Axle Assembly” in this section.

2. Remove the large seal retaining clamp. Discard theclamp.

3. Remove the small seal retaining clamp. Discard theclamp.

3A – 10IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

4. Pry the tripot joint retaining ring from the tripothousing.

5. Remove the tripot housing from the seal.

6. Degrease the tripot assembly.7. Remove the shaft retaining ring using the snap ring

pliers J–8059.

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 11

DAEWOO V–121 BL4

8. Remove the tripot and the tripot joint retaining ringfrom the axle shaft.

9. Remove the tripot joint seal from the axle shaft.

Installation Procedure

Tools RequiredJ–35566 Seal Clamp Pliers1. Install a new small seal retaining clamp onto the

seal. Do not crimp the seal retaining clamp.2. Install the seal onto the axle shaft.3. Install the tripot joint retaining ring and the tripot

onto the axle shaft.

4. Install the shaft retaining ring onto the axle shaftusing the snap ring pliers J–8059.

3A – 12IAUTOMATIC TRANSAXLE DRIVE AXLE

DAEWOO V–121 BL4

5. Fill the tripot housing with 195 to 215 g (6.9 to 7.6ounces) of the recommended grease. Repack thetripot with 195 to 215 g (6.9 to 7.6 ounces) of therecommended grease.

6. Install the tripot housing onto the tripot assembly.

7. Install the tripot joint retaining ring into the tripothousing.

8. Install a new large seal retaining clamp. Crimp thelarge seal retaining clamp using the seal clamp pli-ers J–35566.

9. Crimp the new small seal retaining clamp using theseal clamp pliers J–35566.

10. Install the drive axle shaft to the vehicle. Referto”Drive Axle Assembly” in this section.

AUTOMATIC TRANSAXLE DRIVE AXLE 3A – 13

DAEWOO V–121 BL4

GENERAL DESCRIPTIONAND SYSTEM OPERATION

FRONT DRIVE AXLEGeneral DescriptionDrive axles are flexible shaft assemblies that transmitrotational force from the transaxle to the front–wheel as-semblies. Each axle assembly consists of an inner and an

outer constant–velocity joint connected to an axle shaft.The inner joint is completely flexible and has the ability tomove in and out. The outer joint is also flexible, but it can-not move in and out.

The drive axles use one type of outboard joint and one typeof inboard joint. The inboard ends of both drive axles incor-porate a female spline that installs over a stub shaft pro-truding from the transaxle.

SECTION 4

USAGE AND CAPACITY OF FUSES

USAGE AND CAPACITY OF FUSESW4–2

1. ENGINE COMPARTMENT RELAY AND FUSE BOX

1) POSITION OF RELAY AND FUSE

Front View

Rear View

2) USAGE OF FUSES IN ENGINE COMPARTMENT FUSE BOX

Power Supply Classification Fuse No Capacity Usage

Ef 1 30A Battery Main (F10, F11, F12, F13, F14)

Ef 2 30A Blower Motor

SB(Slow–Blown Ef 3 20A Cooling Fan Low Speed

30 BAT( )

SB(Slow–BlownFuse) Ef 4 40A ABS (Option)

30 BAT(+)Ef 5 30A Ignition–2(Key)

Ef 6 30A Ignition–1(Key)

Circuit Brake Ef 7 20A Ignition Relay ”2”(Power Window)

SB Fuse Ef 8 20A Cooling Fan High Speed

Ef 9 10A Not Used

Spare Ef 10 15A Not UsedSpare

Ef 11 20A Not Used

30 BAT(+) Ef 12 15A Hazard

SEf 13 25A Not Used

SpareEf 14 30A Not Used

30 BAT(+) Ef 15 30A Defroster

Ef 16 15A DIS

IGN 1 (15)Ef 17 15A Injector

IGN 1 (15)Ef 18 Not Used

Ef 19 15A Fuel pump

Ill i ti (58)Ef 20 10A Illumination RH

Illumination (58)Ef 21 10A Illumination LH

Ef 22 15A ECM

30 BAT(+) Blade Type Fuse Ef 23 – Not Used30 BAT(+) Blade Type Fuse

Ef 24 15A Brake Lamp (Stop Lamp)

Li ht (58)Ef 25 10A Head Lamp Hi Beam RH

Light (58)Ef 26 10A Head Lamp Low Beam RH

IGN 2(15A) Ef 27 10A Electric Mirror Heat

30 BAT( )Ef 28 15A Central Door Locking

30 BAT(+)Ef 29 15A ABS, Cluster, Remind S/W, Clock

Li ht (58)Ef 30 10A Heat Lamp Hi Beam LH

Light (58)Ef 31 10A Heat Lamp Low Beam LH

IGN 2(15A) Ef 32 10A Electric Mirror, Heating Mat

Ef 33 10A Air Conditioner

Ef 34 25A Head Lamp

30 BAT(+) Ef 35 10A Horn30 BAT(+)

Ef 36 – Not Used

Ef 37 15A Fog Lamp

Diode D 38 – A/C Compressor

4–3WUSAGE AND CAPACITY OF FUSES

2. PASSENGER ROOM FUSE BOX1) POSITION OF FUSE AND RELAY

2) USAGE OF FUSES IN PASSENGER ROOM FUSE BOX

Power Supply Classification Fuse No Capacity Usage

F1 15A PCM, Ignition Relay ”1”

F2 10A Airconditioning SystemF3 15A Hazard, Clock, DRL

15 IGN ”1” ONF4 25A Wiper System

15 IGN ”1” ONF5 10A Cluster, ABS, Chime Bell, PRND Switch, Brake

F6 10A SDM(Air Bag)F7 10A Reverse(Back Up) Lamp

Blade TypeF8 10A Cruise Control

15C ACCBlade Type

F9 15A Audio, Cigarette Lighter, Key & BTSI

F10 15A Auto Antenna, AudioF11 – Not Used

BAT+ 30A F12 – Not UsedBAT+ 30AF13 15A Anti Theft

F14 10A DLC ”16” Terminal

System VoltageF15 10A ABS, A/C, Defroster, Ignition Relay ”2”

System VoltageF16 10A ABS

*W30 : BAT(+) Power Supply Through Ef1.

USAGE AND CAPACITY OF FUSESW4–4

3. POSITION OF CONTROL UNIT, RELAY AND PART NUMBER1) ENGINE ROOM FUSE BOX

Part Name Part No Remarks

Fuel Pump Relay 96190187 4 Pin

Fog Lamp Relay 96190187

Horn Relay 96190187

Illumination Relay 96190187

Head Lamp Relay 96190187

A/C Compressor Relay 96190187

Rear Window Defroster Relay 96190189 4 Pin

Radiator Cooling Fan High Speed Relay 96190189

Radiator Cooling Fan Low Speed Relay 96190189

IGN 1 Relay 96190189

IGN 2 Relay 96190189

2) PASSENGER ROOM FUSE BOX

Part Name Part No RemarksABS Relay 12088595

3) BEHIND DRIVER LEG ROOM CONNECTOR HOLDER

Part Name Part No Remarks

Blinker Unit(Turn Signal Relay) 96312545

Wiper Relay 96250544

Blower Motor 4th Speed Relay 96190189

BTSI & Key Interlock Unit 96312299

4) UPPER DRIVER LEG ROOM

Part Name Part No Remarks

Chime Bell 96219056

5) BEHIND LEFT HEAD LAMP

Part Name Part No RemarksRadiator Cooling Fan Control Relay 96312958

6) BEHIND DRIVER SIDE LEFT KICK PANEL

Part Name Part No Remarks

E B C M 96313430

Central Door Locking Relay 96312298

7) FLOOR PANEL BEHIND I/P CENTER PART

Part Name Part No Remarks

Anti–Theft Control Unit 96190181

DRL (Day Time Runing Light) Module 96240514

FLOOR PANEL BELOW FRONT CONSOLE

Part Name Part No Remarks

S D M 96312354

SECTION : 4A

HYDRAULIC BRAKESCAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a toolor equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will helpprevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

TABLE OF CONTENTSSPECIFICATIONS 4A–1. . . . . . . . . . . . . . . . . . . . . . . . . .

GENERAL SPECIFICATIONS 4A–1. . . . . . . . . . . . . . .

FASTENER TIGHTENING SPECIFICATIONS 4A–2.

COMPONENT LOCATOR 4A–3. . . . . . . . . . . . . . . . . . . .

BRAKE SYSTEM (ABS) 4A–3. . . . . . . . . . . . . . . . . . . .

BRAKE SYSTEM (NON–ABS) 4A–4. . . . . . . . . . . . . .

DIAGNOSIS 4A–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

BRAKE SYSTEM TESTING 4A–5. . . . . . . . . . . . . . . .

BRAKE HOSE INSPECTION 4A–5. . . . . . . . . . . . . . . .

WARNING LAMP OPERATION 4A–5. . . . . . . . . . . . . .

BRAKE LAMP WARNING CIRCUIT DIAGNOSIS 4A–6

MAINTENANCE AND REPAIR 4A–10. . . . . . . . . . . . . .

ON–VEHICLE SERVICE 4A–10. . . . . . . . . . . . . . . . . . . .

MANUAL BLEEDING THE BRAKES 4A–10. . . . . . . .

PRESSURE BLEEDING THE BRAKES 4A–13. . . . .

BRAKE HOSE REAR 4A–14. . . . . . . . . . . . . . . . . . . . .

BRAKE HOSE FRONT 4A–15. . . . . . . . . . . . . . . . . . .

STOPLAMP SWITCH 4A–17. . . . . . . . . . . . . . . . . . . . .

BRAKE PEDAL 4A–17. . . . . . . . . . . . . . . . . . . . . . . . . .

GENERAL DESCRIPTION AND SYSTEMOPERATION 4A–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HYDRAULIC FLUID 4A–19. . . . . . . . . . . . . . . . . . . . . . .

SPECIFICATIONS

GENERAL SPECIFICATIONS

Application 2.0 DOHC Engine

Millimeters Inches

Brake Drums:

Inside DiameterMaximum Rebore Di-ameterOut–of–Round

2002010.08

7.877.91

0.0032

Front Brake Rotors:

Discard ThicknessLateral Runout(Installed)Rotor DiameterRotor Thickness (New)Thickness Variation

22.000.030256

24.000.005

0.870.00110.070.95

0.0005

4A – 2IHYDRAULIC BRAKES

DAEWOO V–121 BL4

Application

InchesMillimeters

Rear Brake Rotors:

Discard ThicknessLateral Runout(Installed)Rotor DiameterRotor Thickness (New)Thickness Variation

8.40.03

258.0010.400.005

0.330.00410.160.41

0.0004

Master Cylinder:

Bore Diameter (Nomi-nal)Bore Diameter (Maxi-mum)

23.8123.86

0.9370.937

Caliper:

Minimum Piston Diam-eter (Front)Minimum Piston Diam-eter (Rear)

57.0035.00

2.2441.377

Wheel Cylinder Diameter:

MaximumNominal

––

––

FASTENER TIGHTENING SPECIFICATIONS

Application Nm Lb–Ft Lb–In

Bleeder Screw 8 – 53

Brake Lines 16 12 –

Front Disc Brake Hose–to–Caliper Bolt 40 30 –

Rear Disc Brake Hose–to–Caliper Bolt 32 24 –

Shaft Nut 18 13 –

HYDRAULIC BRAKES 4A – 3

DAEWOO V–121 BL4

COMPONENT LOCATOR

BRAKE SYSTEM (ABS)

1. RH Rear Brake Hose2. RH 3rd Rear Brake Pipe3. Clip4. 2nd Rear Brake Pipe (A)5. 2nd Front Brake Pipe6. RH Front Brake Hose7. 2nd Rear Brake Pipe (B)8. ABS Modulator9. Bracket

10. Front Brake Pipe11. LH Front Brake Hose12. Connector13. 1st Rear Brake Pipe (A)14. 1st Front Brake Pipe15. 1st Rear Brake Pipe (B)16. LHD Master Cylinder/Booster Assembly17. LH Rear Brake Hose18. LH 3rd Rear Brake Pipe

4A – 4IHYDRAULIC BRAKES

DAEWOO V–121 BL4

BRAKE SYSTEM (NON–ABS)

1. RH Rear Brake Hose2. RH 3rd Rear Brake Pipe3. Clip4. 2nd Rear Brake Pipe5. 2nd Front Brake Pipe6. RH Front Brake Hose7. 2nd Rear Brake Pipe8. Front Brake Pipe

9. LH Front Brake Hose10. Connector11. 1st Rear Brake Pipe (A)12. 1st Front Brake Pipe13. 1st Rear Brake Pipe (B)14. LHD Master Cylinder/Booster Assembly15. LH Rear Brake Hose16. LH 3rd Rear Brake Pipe

HYDRAULIC BRAKES 4A – 5

DAEWOO V–121 BL4

DIAGNOSIS

BRAKE SYSTEM TESTINGBrakes should be tested on a dry, clean, reasonablysmooth and level roadway. A true test of brake perfor-mance cannot be made if the roadway is wet, greasy, orcovered with loose dirt whereby all tires do not grip theroad equally. Testing will also be adversely affected if theroadway is crowned so as to throw the weight so roughlythat the wheels tend to bounce.

Test the brakes at different vehicle speeds with both lightand heavy pedal pressure; however, avoid locking thebrakes and sliding the tires. Locked brakes and slidingtires do not indicate brake efficiency since heavily braked,but turning, wheels will stop the vehicle in less distancethan locked brakes. More tire–to–road friction is presentwith a heavily–braked, turning tire than with a sliding tire.

Because of the high deceleration capability, a firmer pedalmay be felt at higher deceleration levels.

There are three major external conditions that affect brakeperformance:

Tires having unequal contact and grip of the roadwill cause unequal braking. Tires must be equallyinflated, and the tread pattern of the right and theleft tires must be approximately equal.

Unequal loading of the vehicle can affect the brakeperformance since the most heavily loaded wheelsrequire more braking power, and thus more brakingeffort, than the others.

Misalignment of the wheels, particularly conditionsof excessive camber and caster, will cause thebrakes to pull to one side.

To check for brake fluid leaks, hold constant foot pressureon the pedal with the engine running at idle and the shiftlever in NEUTRAL. If the pedal gradually falls away withthe constant pressure, the hydraulic system may be leak-ing. Perform a visual check to confirm any suspectedleaks.

Check the master cylinder fluid level. While a slight dropin the reservoir level results from normal lining wear, an ab-normally low level indicates a leak in the system. The hy-draulic system may be leaking either internally or external-ly. Refer to the procedure below to check the mastercylinder. Also, the system may appear to pass this testwhile still having a slight leak. If the fluid level is normal,check the vacuum booster pushrod length. If an incorrectpushrod length is found, adjust or replace the rod.

Check themaster cylinder using the following procedure:

Check for a cracked master cylinder casting orbrake fluid leaking around the master cylinder.Leaks are indicated only if there is at least one dropof fluid. A damp condition is not abnormal.

Check for a binding pedal linkage and for an incor-rect pushrod length. If both of these parts are insatisfactory condition, disassemble the master cyl-inder and check for an elongated or swollen primarycylinder or piston seals. If swollen seals are found,substandard or contaminated brake fluid should besuspected. If contaminated brake fluid is found, allthe components should be disassembled andcleaned, and all the rubber components should bereplaced. All of the pipes must also be flushed.

Improper brake fluid, or mineral oil or water in the fluid,may cause the brake fluid to boil or cause deterioration ofthe rubber components. If the primary piston cups in themaster cylinder are swollen, then the rubber parts havedeteriorated. This deterioration may also be evidenced byswollen wheel cylinder piston seals on the drum brakewheels.

If deterioration of rubber is evident, disassemble all the hy-draulic parts and wash the parts with alcohol. Dry theseparts with compressed air before reassembly to keep alco-hol out of the system. Replace all the rubber parts in thesystem, including the hoses. Also, when working on thebrake mechanisms, check for fluid on the linings. If exces-sive fluid is found, replace the linings.

If the master cylinder piston seals are in satisfactory condi-tion, check for leaks or excessive heat conditions. If theseconditions are not found, drain the fluid, flush the mastercylinder with brake fluid, refill the master cylinder, andbleed the system. Refer to”Manual Bleeding the Brakes”or”Pressure Bleeding the Brakes” in this section.

BRAKE HOSE INSPECTIONThe hydraulic brake hoses should be inspected at leasttwice a year. The brake hose assembly should be checkedfor road hazard damage, cracks, chafing of the outer cov-er, and for leaks or blisters. Inspect the hoses for properrouting and mounting. A brake hose that rubs on a suspen-sion component will wear and eventually fail. A light anda mirror may be needed for an adequate inspection. If anyof the above conditions are observed on the brake hose,adjust or replace the hose as necessary.

WARNING LAMP OPERATIONThis brake system uses a BRAKE warning lamp locatedin the instrument panel cluster. When the ignition switchis in the START position, the BRAKE warning lamp shouldglow and go OFF when the ignition switch returns to theRUN position.

The following conditions will activate the BRAKE lamp:

Parking brake applied. The light should be ONwhenever the parking brake is applied and the igni-tion switch is ON.

Low fluid level. A low fluid level in the master cylin-der will turn the BRAKE lamp ON.

As a test of the lamp circuit, vehicles with antilockbrakes will momentarily illuminate the lamp forabout 4 seconds when the ignition

4A – 6IHYDRAULIC BRAKES

DAEWOO V–121 BL4

BRAKE LAMP WARNING CIRCUIT DIAGNOSIS

Test Description

The number(s) below refer to step(s) on the diagnostictable.

1. When the ignition is turned ON, the brake warninglamp should initially illuminate and then dim for ABSequipped vehicles. This is done as a bulb check.On vehicles that are not equipped with ABS, thebrake warning lamp should only illuminate wheneither the brake fluid reservoir is low or the parkingbrake is applied.

7. The brake fluid level switch is a normally openswitch. If the brake warning lamp is off after discon-necting the switch, the brake fluid level switch isstuck closed.

9. If the brake warning lamp is still on after discon-necting the parking brake switch, there is a short toground in the wire to the parking brake switch.

12. If the other checks have been properly performedand the brake warning lamp is off after disconnect-ing the electronic brake control module (EBCM) J1connector, the EBCM is faulty.

19. If the brake warning lamp does not operate whileperforming any of the functions, the fault should bein the ignition feed to the circuit.

24. This step determines if the problem is in the ignitionfeed to the circuit or in the instrument cluster.

30. The brake warning lamp should illuminate whenjumpering the parking brake connector to ground.

32. If the brake warning lamp is on after jumpering thebrake fluid level switch terminals, the switch isfaulty.

HYDRAULIC BRAKES 4A – 7

DAEWOO V–121 BL4

Brake Lamp Warning Circuit Diagnosis

Step Action Value(s) Yes No

1 Turn the ignition ON.Is the brake warning lamp always on?

Go toStep 2 Go toStep 18

2 Check the ABS warning lamp.Is the ABS warning lamp also on?

Go toStep 3 Go toStep 4

3 Use a scan tool to check for diagnostic trouble codes(DTCs) and follow the procedures for any DTCsfound.Is the lamp still on?

Go toStep 4 System OK

4 Release the parking brake fully.Is the lamp off?

System OK Go toStep 5

5 Check the brake fluid level.Is the fluid level OK?

Go toStep 7 Go toStep 6

6 1. Fill the brake fluid reservoir with clean DOT 3equivalent hydraulic fluid.

2. Replace the cap on the fluid reservoir.Is the lamp on?

Go toStep 7 System OK

7 Disconnect the harness connector from the brakefluid level switch.Is the lamp on?

Go toStep 9 Go toStep 8

8 Replace the brake fluid level switch.Is the repair complete?

System OK

9 1. Connect the brake fluid level switch.2. Disconnect the parking brake switch.Is the lamp on?

Go toStep 11 Go toStep 10

10 Replace the parking brake switch.Is the repair complete?

System OK

11 Connect the parking brake switch.Is the vehicle equipped with ABS?

Go toStep 12 Go toStep 14

12 1. Turn the ignition OFF.2. Disconnect the electronic brake control module

(EBCM) connector.3. Turn the ignition ON.Is the lamp on?

Go toStep 14 Go toStep 13

13 Replace the electronic brake control module(EBCM).Is the repair complete?

System OK

14 1. Turn the ignition OFF.2. Connect the EBCM connector.3. Check for a short to ground in the wiring be-

tween the instrument cluster terminal A2 andthe brake fluid level switch.

Is the problem found?

Go toStep 17 Go toStep 15

15 Check for a short to ground in the wiring between theinstrument cluster terminal A2 and the parking brakeswitch.Is the problem found?

Go toStep 17 Go toStep 16

4A – 8IHYDRAULIC BRAKES

DAEWOO V–121 BL4

Step NoYesValue(s)Action

16 Check for a short to ground in the wiring between theinstrument cluster terminal A2 and the EBCM con-nector terminal 21.Is the problem found?

Go toStep 17 Go toStep 18

17 Repair the wiring as needed.Is the repair complete?

System OK

18 Check the brake lamp after doing each of the follow-ing functions: Apply the parking brake. Remove the cap from the brake fluid reservoir. On vehicles equipped with ABS, command the

lamp on using a scan tool.Does the brake warning lamp operate for all of theseconditions?

System OK Go toStep 19

19 When the operations listed in step 18 were per-formed, the brake warning lamp did not function.Did the brake warning lamp fail to light for all of theoperations listed in step 18?

Go toStep 20 Go toStep 27

20 1. Turn the ignition OFF.2. Inspect the kick panel fuse F5.Is the fuse OK?

Go toStep 22 Go toStep 21

21 Replace the fuse.Is the repair complete?

System OK

22 Inspect the brake warning lamp bulb.Is the bulb OK?

Go toStep 24 Go toStep 23

23 Replace the bulb.Is the repair complete?

System OK

24 1. Disconnect the instrument cluster connector.2. Turn the ignition ON.3. Measure the voltage at the instrument cluster

connector terminal A2.Does the voltagemeasurewithin the value specified?

11–14 v Go toStep 25 Go toStep 26