GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

Faulty cylinder head gaskets and/or cracking or other damage to the cylinder heads and engine block cooling system passages - Refer to Diagnostic Starting Point - Engine Cooling in Engine Cooling.

Coolant consumption may or may not cause the engine to overheat.

    • Inspect for spark plugs saturated by coolant. Refer to Spark Plug Inspection in Engine Controls - 5.3L.
    • Perform a cylinder leak down test. Refer to Cylinder Leakage Test .
    • Inspect the cylinder heads and engine block for damage to the coolant passages and/or a faulty head gasket. Refer to Coolant in Combustion Chamber .
    • Repair or replace as required.