Symptom Diagnosis

Symptom checks cannot be used properly unless problem occurs while vehicle is being tested. To reduce diagnostic time, ensure steps in the following articles, in the ENGINE PERFORMANCE Section were performed before diagnosing a symptom.

• BASIC TESTING
• TESTS W/CODES

Recommended system and component checks may not apply to all vehicles. Symptoms available for diagnosis include following.

• Engine Will Not Start
• Difficult Cold Start
• Fast Idle Out Of Specification
• Rough Idle When Warm
• Idle RPM High When Warm
• Idle RPM Low When Warm
• Stalling During Warm-Up
• Stalling After Warm-Up
• Misfire Or Rough Operation
• Emission Test Failure
• Lack Of Power