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 BASIC TESTING and TESTS W/CODES articles were performed before diagnosing a symptom. Symptoms available for diagnosis include:

• Engine Won't Start
• Engine Starts But Stops
• Rough or Unstable Idle
• Poor Response On Acceleration
• Engine Hesitates or Misses
• Poor Fuel Mileage
• Lack of Power
• CO Too Low or Too High