Symptom Diagnosis

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure BASIC steps in the BASIC TESTING article and that the self-diagnostic test procedures in the TESTS W/CODES article were performed before diagnosing a symptom. The following symptoms are available for diagnosis in this article.

• Will Not Start (Cranks Okay)
• Difficult Start (Cranks Okay)
• Engine Surges
• Rough Or Unstable Idle
• Excessive Fast Idle
• Engine Stalls
• Engine Lacks Power
• Engine Misfires Or Hesitates
• Afterburn In Exhaust System
• Poor Fuel Mileage
• Detonation Or Knocking
• Fails Emission Test