Important Preliminary Checks
Before Starting
Before using this section 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. |
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 and physical
check. The importance of this step cannot be stressed strongly enough. This
step can lead to correcting a problem without further checks and can
save valuable time. This check should include:
| • | PCM grounds for the following conditions: |
| • | Vacuum hoses for the following conditions: |
| - | Proper connections as shown on Vehicle Emission Control Information
label |
| • | Air leaks at the following components: |
| - | Intake manifold sealing surfaces |
| • | Wiring for the following conditions: |
| • | Use the following tables when diagnosing a symptom complaint: |