ENGINE COMPRESSION
Check engine compression with engine at normal operating temperature, all spark plugs removed and throttle wide open.
| Application | Specification |
|---|
| Normal Compression Pressure |
| 1.0L | 199 psi (14.0 kg/cm 2 ) |
| 1.3L | 192 psi (13.5 kg/cm 2 ) |
| 1.8L | 218 psi (15.3 kg/cm 2 ) |
| 1.9L | 185-205 psi (13.0-14.4 kg/cm 2 ) |
| 2.2L, 2.4L, 3.0L, 3.1L, 3.4L, 3.8L, 4.0L, 4.6L & 5.7L | (1) |
| 3.5L | (2) |
| Minimum Compression Pressure |
| 1.0L & 1.3L | 156 psi (11.0 kg/cm 2 ) |
| 1.8L | 145 psi (10.2 kg/cm 2 ) |
| 1.9L | 180 psi (12.7 kg/cm 2 ) |
| 2.2L, 2.4L, 3.0L, 3.1L, 3.4L, 3.8L, 4.0L, 4.6L & 5.7L | (1) |
| 3.5L | (2) |
| (1) Lowest compression reading should not be less than 70 percent of highest compression reading. No cylinder compression reading should be less than 100 psi (7.0 kg/cm 2 ). (2) Lowest compression reading should not be less than 70 percent of highest compression reading. No cylinder compression reading should be less than 140 psi (9.8 kg/cm 2 ). |
| (1) | Lowest compression reading should not be less than 70 percent of highest compression reading. No cylinder compression reading should be less than 100 psi (7.0 kg/cm 2 ). |
| (2) | Lowest compression reading should not be less than 70 percent of highest compression reading. No cylinder compression reading should be less than 140 psi (9.8 kg/cm 2 ). |
COMPRESSION SPECIFICATIONS
VALVE CLEARANCE
| Application | In. (mm) |
|---|
| Prizm |
| Intake | (1) .006-.010 (.15-.25) |
| Exhaust | (1) .010-.014 (.25-.35) |
| All Others | (2) |
| (1) Adjustments are made with engine cold 77°F (25°C). (2) Equipped with hydraulic lifters. Adjustment is not required. |
| (1) | Adjustments are made with engine cold 77°F (25°C). |
| (2) | Equipped with hydraulic lifters. Adjustment is not required. |
VALVE CLEARANCE SPECIFICATIONS
HIGH TENSION WIRE RESISTANCE
| Application | Ohms |
|---|
| 1.0L | 3000-6700 Per Foot |
| 1.3L | 1200-3000 Per Foot |
| 1.8L | 25,000 Or Less |
| 1.9L | Less Than 12,000 |
| 2.2L | Less Than 30,000 |
| 3.0L | 2000-3000 |
| 3.1L | 5000-8000 |
| 3.4L & 3.8L | (1) |
| 4.0L & 4.6L | 15,000 Or Less |
| (1) Replace wire if resistance exceeds 600 ohms per foot. |
| (1) | Replace wire if resistance exceeds 600 ohms per foot. |
HIGH TENSION WIRE RESISTANCE
SPARK PLUGS
| Application | Spark Plug Type | Spark Plug No. |
|---|
| 1.0L | AC | R42XLS |
| 1.3L | Denso | K20PR-U11 |
| NGK | BKR6E-11 |
| 1.8L | Denso | K16TR11 |
| NGK | BKR5EKB11 |
| 1.9L SOHC | AC | 41-628 |
| 1.9L DOHC | AC | 41-627 |
| 2.2L | AC | 41-928 |
| 2.4L | AC | 41-942 |
| 3.0L | Bosch | FLR9LTE |
| 3.1L & 3.4L | AC | 41-940 |
| 3.5L | GM | 12556183 |
| 3.8L | AC | 41-921 |
| 4.0L | AC | 41-950 |
| 4.6L | AC | 41-929 |
| 5.7L | AC | 41-931 |
| Application | Gap In. (mm) | Torque Ft. Lbs. (N.m) |
|---|
| 1.0L & 1.3L | .040-.043 (1.0-1.1) | 21 (28) |
| 1.8L | .043 (1.1) | 13 (18) |
| 1.9L | .040 (1.0) | 20 (27) |
| 2.2L | .050 (1.27) | 13 (18) |
| 2.4L | .050 (1.27) | 13 (18) |
| 3.0L | .035-.043 (.9-1.1) | 19 (25) |
| 3.1L & 3.8L | .060 (1.52) | 20 (27) |
| 3.4L | .060 (1.52) | 11 (15) |
| 3.5L | .050 (1.27) | 15 (20) |
| 4.0L & 4.6L | .050 (1.27) | 11 (15) |
| 5.7L | .060 (1.52) | (1) |
| (1) Tighten to 15 ft. lbs. (20 N.m) when using NEW cylinder head. Tighten to 11 ft. lbs. (15 N.m) for all subsequent installations. |
| (1) | Tighten to 15 ft. lbs. (20 N.m) when using NEW cylinder head. Tighten to 11 ft. lbs. (15 N.m) for all subsequent installations. |
SPARK PLUG SPECIFICATIONS
FIRING ORDER
Scheme 1
Scheme 1: Firing Order (1.0L)
Scheme 2
Scheme 2: Firing Order (1.3L, 1.8L, 1.9L, 2.2L & 2.4L)
Scheme 3
Scheme 3: Firing Order (3.0L)
Scheme 4
Scheme 4: Firing Order (3.1L & 3.4L)
Scheme 5
Scheme 5: Firing Order (3.5L)
Scheme 6
Scheme 6: Firing Order (3.8L - Except "F" Body)
Scheme 7
Scheme 7: Firing Order (3.8L - "F" Body)
Scheme 8
Scheme 8: Firing Order (4.0L & 4.6L)
Scheme 9
Scheme 9: Firing Order (5.7L)
IGNITION TIMING
Note. All models except Metro & Firefly (Canadian) 1.0L are equipped with an electronic computer-controlled ignition system. Timing on these systems is not adjustable. On Metro & Firefly (Canadian) 1.0L, move distributor to adjust ignition timing. Refer to underhood emissions label for specification.
FUEL PUMP
| Application | (1) KOEO psi (kg/cm 2 ) |
|---|
| 1.0L | 23-31 (1.6-2.2) |
| 1.3L | 39-44 (2.7-3.1) |
| 1.8L | 44-50 (3.1-3.5) |
| 1.9L | 40-55 (2.8-3.9) |
| 2.2L, 3.1L, 3.4L & 3.5L | 41-47 (2.9-3.3) |
| 2.4L |
| With EGR | 41-47 (2.9-3.3) |
| Without EGR | 52-58 (3.7-4.1) |
| 3.0L | 40-48 (2.8-3.4) |
| 3.8L, 4.0L & 4.6L | 48-55 (3.4-3.9) |
| 5.7L | 55-60 (3.9-4.2) |
| (1) KOEO is ignition ON and engine OFF. |
| (1) | KOEO is ignition ON and engine OFF. |
INJECTOR RESISTANCE
| Application | (1) Ohms |
|---|
| 1.0L | 10.5-11.5 |
| 1.3L | 12-13 |
| 1.8L | 13.4-14.4 |
| 1.9L | 11.5-12.5 |
| 2.2L | 1.9-2.2 |
| 2.4L | 11.4-12.6 |
| 3.0L | (2) |
| 3.1L, 3.4L, 3.8L, 4.0L, 4.6L & 5.7L | 11.4-12.6 |
| 3.5L | 11.6-12.8 |
| (1) Injector resistance specification is at 50-95°F (10-35°C). (2) Information is not available from manufacturer. |
| (1) | Injector resistance specification is at 50-95°F (10-35°C). |
| (2) | Information is not available from manufacturer. |
INJECTOR RESISTANCE SPECIFICATIONS
IDLE SPEED & MIXTURE
Note. Idle mixture is controlled by Powertrain Control Module (PCM). Idle speed is preset by manufacturer and is not adjustable.
THROTTLE POSITION (TP) SENSOR
Note. TP sensor is not adjustable unless specified otherwise. For further testing procedures, refer to appropriate SELF-DIAGNOSTICS or SYSTEM & COMPONENT TESTING article.
Note. On Corvette, throttle control is electronic with NO mechanical link from engine to accelerator pedal. The PCM and Throttle Actuator Control (TAC) module monitor the position of accelerator pedal based on signals from a nonadjustable Accelerator Pedal Position (APP) sensor. The APP sensor is mounted above accelerator pedal.
| Application | (1) Volts |
|---|
| 1.0L | (2) |
| 1.3L | 0.2-1.0 To 3.0-4.8 |
| 1.8L | 0.3-0.8 To 3.2-4.9 |
| 1.9L | 0.2-0.6 To 4.5-4.9 |
| 2.2L & 2.4L | 0.35-4.65 |
| 3.0L | 0.3-0.9 To 4.0-5.0 |
| 3.1L, 3.4L, 3.5L, 3.8L, 4.0L & 4.6L | (3) |
| 5.7L |
| "F" Body | (3) |
| "Y" Body |
| Sensor No. 1 | (4) |
| Sensor No. 2 | (5) |
| (1) Voltage range is from idle position to wide open throttle position. (2) Ensure engine is at normal operating temperature. Connect a DVOM (backprobe) between ground and TP sensor signal circuit at PCM. See appropriate wiring diagram in WIRING DIAGRAMS article. Voltage reading should be 0.98-1.02 volts with a .140" (3.5 mm) feeler gauge placed between throttle stop screw and throttle lever. Adjust or replace as necessary. (3) Voltage range is less than one volt at closed throttle to greater than 4 volts at wide open throttle. (4) Voltage range is less than one volt at closed throttle to 3.5 volts at wide open throttle. (5) Voltage range is 3.8 volts at closed throttle to less than one volt at wide open throttle. |
| (1) | Voltage range is from idle position to wide open throttle position. |
| (2) | Ensure engine is at normal operating temperature. Connect a DVOM (backprobe) between ground and TP sensor signal circuit at PCM. See appropriate wiring diagram in WIRING DIAGRAMS article. Voltage reading should be 0.98-1.02 volts with a .140" (3.5 mm) feeler gauge placed between throttle stop screw and throttle lever. Adjust or replace as necessary. |
| (3) | Voltage range is less than one volt at closed throttle to greater than 4 volts at wide open throttle. |
| (4) | Voltage range is less than one volt at closed throttle to 3.5 volts at wide open throttle. |
| (5) | Voltage range is 3.8 volts at closed throttle to less than one volt at wide open throttle. |
TP SENSOR ADJUSTMENT VOLTAGE
