GM Service Manual Online
For 1990-2009 cars only

Checks

Action

DEFINITION: Engine cranks OK, but does not start for a long time. May eventually run, or may start but immediately dies.

Preliminary

    • Verify that the driver is using the correct starting procedure as described in the owners manual.
    • Refer to Symptoms - Engine Controls .
    • Search for service bulletins.

Sensor/System

    • Inspect the engine coolant temperature (ECT) sensor for a skewed reading. Install a scan tool and compare the ECT with the intake air temperature (IAT) on a cold engine. The ECT and IAT should be within ± 3°C (5°F) of each other. Inspect the resistance of the ECT sensor if the temperature is out of range with the IAT sensor. Refer to Temperature Versus Resistance . If the ECT sensor resistance is not within the specification, refer to DTC P0117 or DTC P0118 .
    • Inspect for proper operation of the crank sensor.
    • Inspect for proper operation of the manifold absolute pressure (MAP) sensor.
    • Inspect for proper operation of the throttle position (TP) sensor.
    • Inspect for proper operation of the idle air control (IAC) valve.

Fuel System

    • Inspect for adequate fuel level.
    • Inspect the fuel pump relay circuit for proper operation. Refer to Fuel Pump Electrical Circuit Diagnosis .
    • Inspect for incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Inspect the in-tank fuel pump check valve. The in-tank fuel pump check valve may be malfunctioning, causing the fuel in the lines to drain back to the fuel tank after the engine is stopped. Refer to Fuel System Diagnosis .

Ignition System

    • Inspect for proper ignition voltage output with a J 26792 Spark Tester or equivalent.
    • Inspect the spark plugs for the following conditions:
       - Wet or fuel fouled
       - Cracks
       - Wear
       - Improper spark plug gap
       - Burned electrodes or heavy deposits
    • If the spark plugs are fuel or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
    • Inspect the ignition control module (ICM) for proper ground connection.
    • Inspect the ignition coils for cracks or carbon tracking.
    • Inspect the spark plug wires for proper resistance and condition.

Engine Mechanical

Inspect the engine for the following engine mechanical problems:

    • Low compression--Refer to Engine Compression Test in Engine Mechanical 2.2L (L43).
    • Leaking cylinder head gasket
    • Worn or a incorrect camshaft

Additional Inspections

If all procedures have been completed and no malfunctions have been found, review and inspect the following items:

    • All electrical connections within the suspected circuit and/or systems
    • Scan tool data