GM Service Manual Online
For 1990-2009 cars only

Uncommon Cooling System Problems

Problems not requiring disassembly of the cooling system:

    • Large obstructions that block the radiator or the condenser
    • Auxiliary oil coolers-relocate
    • Ice, mud, or snow-remove
    • Engine oil overfill-check engine oil dipstick
    • Incorrect radiator for application-install the correct radiator
    • Missing or damaged air baffle or lower air deflector-repair or replace as necessary

Problems requiring disassembly of the cooling system:

    • An incorrect or damaged fan-repair or replace as necessary
    • Faulty emission system components (could cause overheating at idle)-replace the faulty component
    • Positive Crankcase Ventilation (PCV) valve
    • Thermal Vacuum Valve (TVV)
    • Pressure testing the cooling system with the radiator cap installed
    • A faulty coolant pump-replace the coolant pump
    • Plugged radiator tubes
    • Internal system leaks
    • The head gasket
    • A cracked block
    • The timing chain/belt cover
    • The intake manifold gasket
    • Plugged coolant passages in the cylinder head(s)-remove the head(s) and check visually