BELT TENSION
Adjustment of serpentine belt is not necessary. Belt tension is maintained by spring-tensioned idler pulley (some equipped with belt wear indicator).
ENGINE COMPRESSION
Check engine compression with engine at normal operating temperature, all spark plugs removed and throttle wide open.
| Application | Psi (kPa) |
|---|---|
| Normal Compression Pressure | (1) |
| Minimum Compression Pressure | (2) 100 psi (689 kPa) |
| (1) Information not available from manufacturer. (2) The lowest reading cylinder should not be less than 70 percent of the highest. | |
| (1) | Information not available from manufacturer. |
| (2) | The lowest reading cylinder should not be less than 70 percent of the highest. |
ENGINE COMPRESSION SPECIFICATIONS
VALVE CLEARANCE
Equipped with hydraulic lifters. Adjustment is not required.
HIGH TENSION WIRE RESISTANCE
Ignition coils are connected directly to spark plugs by boots.
SPARK PLUGS
| Application | Spark Plug Type | Spark Plug No. |
|---|---|---|
| All Models | AC | 41-981 or GM P/N 12569190 |
SPARK PLUG TYPE
| Application | Gap - In. (mm) | Torque - Ft. Lbs. (N.m) |
|---|---|---|
| All Models | .042 (1.07). | 15 (20) |
SPARK PLUG SPECIFICATIONS
FIRING ORDER
Note. For firing order, refer to illustration. (Scheme 1)
Scheme 1
IGNITION TIMING
Note. All models are equipped with an electronic computer-controlled ignition system. Timing is not adjustable.
FUEL PUMP
| Application | (1) KOEO - psi (kPa) |
|---|---|
| All Models | 50-60 (345-414) |
| (1) KOEO is ignition key ON and engine OFF. | |
| (1) | KOEO is ignition key ON and engine OFF. |
FUEL PUMP PERFORMANCE
INJECTOR RESISTANCE
| Application | (1) Ohms |
|---|---|
| All Models | 11.0-14.0 |
| (1) DO NOT perform this test if the engine coolant temperature (ECT) is above 94°C (201°F). | |
| (1) | DO NOT perform this test if the engine coolant temperature (ECT) is above 94°C (201°F). |
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. For further testing procedures, perform TP sensor related diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ALERO, CAVALIER, GRAND AM & SUNFIRE - GASOLINE article.
| Application | (1) Specification |
|---|---|
| All Models | (2) |
| (1) Range is from idle to wide open throttle. (2) PCM computes the throttle position (TP) from the TP sensor voltage input. The TP angle will auto zero to zero percent at idle when the TP voltage is below 0.90 volt. The TP angle will read 100 percent at wide open throttle. | |
| (1) | Range is from idle to wide open throttle. |
| (2) | PCM computes the throttle position (TP) from the TP sensor voltage input. The TP angle will auto zero to zero percent at idle when the TP voltage is below 0.90 volt. The TP angle will read 100 percent at wide open throttle. |
TP SENSOR SPECIFICATIONS