Important Preliminary Inspections
Before Starting
Before using this section, you should have performed the Diagnostic System
Check-Engine Controls and determined that the following items are OK:
| • | The engine control module (ECM), malfunction indicator lamp (MIL), and
check engine are operating correctly. |
| • | There are no diagnostic trouble codes (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 Inspection
Several of the symptom procedures call for a careful visual/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:
| • | ECM grounds for the following conditions: |
| • | Vacuum hoses for the following conditions: |
| • | Air leaks at the following components: |
| - | Intake manifold sealing surfaces |
| • | Wiring for the following conditions: |
| • | Use the following tables when diagnosing a symptom complaint: |
