GM Service Manual Online
For 1990-2009 cars only

Checks

Action

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

Preliminary

    • Refer to Important Preliminary Checks Before Starting in Symptoms .
    • Refer to Visual/Physical Checks in Symptoms .
    • Search for bulletins.

Sensor/System

    • Check Engine Coolant Temperature (ECT) sensor for being shifted in value. Install a scan tool and compare the displayed Engine Coolant Temperature with Intake Air Temperature on a cold engine. Check the resistance of the ECT sensor if engine coolant temperature is not within ± 3°C (5°F) of intake air temperature. Refer to Temperature Versus Resistance . If the ECT sensor resistance is not within the specification, refer to DTC P0117 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage or DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage .
    • Check the throttle body inlet screen for foreign objects or damage that may affect the MAF sensor airflow sample. Refer to Throttle Body Air Inlet Screen Replacement .
    • Check the IAC operation using a scan tool. Refer to Idle Air Control (IAC) System Diagnosis .
    • Check the EGR system. Check the for the following conditions:
       - Check the EGR pipes and adapter for vacuum leaks.
       - Remove the EGR valve and check for a stuck open pintle. Refer to Exhaust Gas Recirculation Valve Replacement .

Fuel System

    • Check the fuel pump relay circuit for proper operation. Refer to Fuel Pump Electrical Circuit Diagnosis .
    • Check the fuel pressure.
       - Refer to Fuel System Pressure Test (VIN K) .
       - Refer to Fuel System Pressure Test (VIN 1) .
    • Check the fuel injectors.
    • Check for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

Ignition System

    • Check for proper ignition voltage output using the following steps:
       - Clip the spark tester J 26792 to engine ground.
       - Connect one end of a spark plug wire to the spark tester; leave the other end of the spark plug wire to the coil being tested.
       - Connect one end of another spark plug wire to the other coil tower; connect the other end of the spark plug wire to ground.
       - Crank the engine while observing the spark tester; a spark should be observed.
       - Repeat the above steps for each coil.
    • If spark is not present at the coil(s), check for the following conditions:
       - Inspect the Coil(s) - Cracks, carbon tracking/arcing, or a secondary resistance value outside the specified range.

   Important:: If carbon tracking is detected on any component, replace that component and its mate.

Coil Secondary Resistance
5000 - 8000 ohms (5K - 8K ohms)

       - Inspect the spark plug wires for signs of arcing/cross firing, cracks, carbon tracking, plug boot damage, pinched, incorrect routing, or a resistance value greater than the specified value.

VIN 1 Spark Plug Wires Resistance
3280 - 4921 ohms per meter (1000 ohms - 1500 ohms per foot)

VIN K Spark Plug Wires Resistance
3280 - 4921 ohms per meter (1000 ohms - 1500 ohms per foot)

   Important: Spraying the secondary ignition wires with a light mist of water may help locate an intermittent problem. Ignition components will arc to ground when a secondary component is malfunctioning.

       - Check for a malfunctioning ignition control module.
       - Inspect the ignition system wiring for a loose ignition module feed, a poor ground connection, or damaged system wiring.
    • Remove the spark plugs.
    • Inspect the spark plugs for the following conditions:
       - Check the spark plugs for fouling. Refer to Spark Plug Visual Diagnosis .
       - Check the spark plug for cracks.
       - Refer to Spark Plug Visual Diagnosis .
       - Check the spark plugs for signs of carbon tracking on the porcelain or arcing at the plug wire contact. Refer to Spark Plug Visual Diagnosis .
       - Check the spark plugs for incorrect gap. Refer to Spark Plug Visual Diagnosis .
       - Check the spark plugs for burned or damaged electrodes. Refer to Spark Plug Visual Diagnosis .
       - Check the spark plugs for incorrect heat range. Refer to Maintenance Items .
    • If spark plugs are gas or oil fouled, the cause of the fouling must be determined before replacing the spark plugs. Refer to Spark Plug Visual Diagnosis .

Engine Mechanical

    • Excessive oil in combustion chamber-Leaking valve seals. Refer to Oil Consumption Diagnosis .
    • Low cylinder compression. Refer to Cylinder Leakage Test .
    • For incorrect basic engine parts, refer to Engine Overhaul . Inspect the following:
       - Cylinder heads
       - Camshaft and valve train components
       - Pistons, etc.