- Important Preliminary Checks

BEFORE STARTING
Before using this section you should have performed the On-Board Diagnostic (OBD) System Check and determined that:

1. The Powertrain Control Module (PCM) and the Malfunction Indicator Lamp (MIL)"Service Engine Soon" are functioning correctly.
2. There are no Diagnostic Trouble Codes (DTCs) stored, or there is a DTC but no MIL (Service Engine Soon).

SYMPTOM
Verify the customer complaint, and locate the correct symptom in the table of contents. Check the items indicated under that symptom.

VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful visual/physical check. This check should include:

^ Wiring for proper connections, pinches and cuts.
^ PCM grounds for being clean, tight and in their proper location.
^ Air leaks at throttle body mounting area and intake manifold sealing surfaces.

NOTE: The importance of this step cannot be stressed too strongly. It can lead to correcting a problem without further checks and can save valuable time