Symptom Diagnosis: Notes

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

• Engine Won't 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