Flow of Diagnosis

Inspection and Verification
1. Verify the vehicle owner's concern by trying to duplicate the condition.

2. Inspect to determine if any of the following mechanical concerns apply:

^ Hissing sound or release of pressure as the fuel tank filler cap is removed.

3. If the inspection reveals obvious concern(s) that can be readily identified, service as required.

Evaporative Emission Diagnosis:

4. If the concern(s) remain after the inspection, determine the symptoms and go to the Symptom Chart.