GM Service Manual Online
For 1990-2009 cars only

Checks

Action

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

Preliminary Checks

    • Refer to Symptoms - Engine Controls .
    • Make sure the driver is using the correct starting procedure.

Sensor Checks

Check the engine coolant temperature (ECT) sensor. Use the scan tool in order to compare the engine coolant temperature with the ambient air temperature on a cold engine. If the coolant temperature reading is more than 5 degrees more or less than the ambient air temperature on a cold engine, check for a high resistance in the coolant sensor circuit or the coolant sensor.

Fuel System Checks

    • Check the supply to injection pump. Refer to Fuel System Diagnosis .
    • Check for air in the fuel system.
    • Check the fuel return from the injection pump.
    • Check for engine shut-off solenoid operation.
    • Check the fuel injection nozzles.
    • Check the fuel tank cap vent.
    • Check for an internal injection pump problem.

Electrical System Checks

    • Check glow plug operation. Refer to Glow Plug System Diagnosis .
    • Check for slow cranking speed.

Air Intake System Checks

    • Check the air cleaner and air intake ducts for a restriction.
    • Check for a restriction in turbo charger inlet duct.
    • Check for a restriction in the intake manifold.

Exhaust System Check

Check the exhaust system for possible restriction. Refer to Restricted Exhaust in Engine Exhaust.

Engine Mechanical Checks

Check the engine for the following:

    • Improper valve timing
    • Bent pushrods
    • Worn rocker arms
    • Low compression. Refer to Engine Compression Test in Engine Mechanical.
    • Broken or weak valve springs
    • Worn camshaft lobes

Additional Checks

    • Check for no crank signal.
    • Check the Service Bulletins for control module software updates.