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

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

  1. Inspect for spark plugs saturated by coolant. Refer to Spark Plug Inspection .
  2. Perform a cylinder leak down test. Refer to Cylinder Leakage Test .
  3. 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 .
  4. Repair or replace, as required.