GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 Sonoma Pickup - 4WD 🢒 Engine 🢒 Engine Controls - 2.2L 🢒 Hard Start

Checks

Action

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

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

Sensor/System
    • Inspect the engine coolant temperature (ECT) sensor for being shifted in value. Install a scan tool and compare the engine coolant temperature with the intake air temperature on a cold engine. The ECT and IAT should be within ± 3°C (5°F) of each other. Test 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 Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage or DTC P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage .
    • Test for proper operation of the MAP sensor . Refer to Manifold Absolute Pressure Sensor Output Diagnosis .
    • Test for proper operation of the TP sensor.
    • Test for proper operation of the IAC valve.

Fuel System
    • Inspect for adequate fuel in fuel tank.
    • Inspect for a restricted fuel filter.
    • Test the fuel pump relay circuit for proper operation. Refer to Fuel Pump Electrical Circuit Diagnosis .
    • Test for incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Test for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Test 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
    • Test for proper ignition voltage output with the J 26792 Spark Tester or equivalent.
    • Inspect the spark plugs for the following conditions:
       - Wet or fuel fouled.
       - Cracks.
       - Wear.
       - Improper gap.
       - Burnt 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.
    • Test/inspect the spark plug wires for proper resistance and condition.

Engine Mechanical
    • Test/inspect the engine for the following engine mechanical problems:
       - Low compression.
       - Leaking cylinder head gasket.
       - Worn or a incorrect camshaft.
    • Refer to Base Engine Misfire Diagnosis in Engine Mechanical.

Additional Checks

If all procedures have been completed and no malfunctions have not been found, review and inspect the following items:

    • Visually and physically inspect all electrical connections within the suspected circuit and/or systems.
    • Scan tool data.