Diagnostic Aids

Inspect for the following conditions, which may cause a catalytic converter to degrade:

• An engine misfire
• High engine oil or high coolant consumption
• Retarded spark timing
• A weak or poor spark
• A lean fuel mixture
• A rich fuel mixture
• A damaged oxygen sensor or wiring harness
• If the condition is determined to be intermittent, refer to Testing for Intermittent Conditions and Poor Connections .