GM Service Manual Online
For 1990-2009 cars only

Possible Cause

Correction

Loss of coolant

Check the following areas for possible leakage:

    â€¢ Hoses
    â€¢ Coolant pump
    â€¢ Heater core
    â€¢ Thermostat housing
    â€¢ Radiator
    â€¢ Core plugs
    â€¢ Head gaskets
    â€¢ Intake manifold gaskets

Pressure check the system and cap. Ensure the correct cap is being used.