Important Preliminary Inspections Before Starting

Perform Diagnostic System Check - Engine Controls before using the symptom tables, and verify that all of the following are true:

• The powertrain control module (PCM) and malfunction indicator lamp (MIL) are operating correctly.
• There are no DTCs stored.
• The scan tool data is within the normal operating range, refer to Scan Tool Data List .
• Verify the customer concern and locate the correct symptom in the table of contents. Inspect the items indicated under that symptom.