Symptom Diagnosis

Symptom checks cannot be used properly unless the problem occurs while the vehicle is being tested. To reduce diagnostic time, ensure steps in the BASIC TESTING and the TESTS W/CODES articles were performed before diagnosing a symptom. Symptoms available for diagnosis include:

• Detonation (Engine Knock)
• Difficult Start (Cranks Okay)
• Engine Backfires
• Engine Does Not Start (Fails To Rotate)
• Engine Fails To Idle
• Engine Rotates, But Fails To Start
• Engine Runs Rough (Off Idle)
• Engine Stalls
• Loss Of Power
• Rough Or Unstable Idle