A Important Preliminary Checks

Before Starting
Before using this, you should have performed the Powertrain On-Board Diagnostic (OBD) System Check and determined that the following items are OK:
^ The PCM and MIL, check engine, are operating correctly.
^ There are no DTCs stored.
^ Scan tool data is within normal operating range, refer to the Engine Scan Tool Data List. Scan Tool Data, Normal Values and Definitions
Verify the customer complaint, and locate the correct symptom in the table of contents. Check the items indicated under that symptom.