Important Preliminary Checks Before Starting
Before using the Symptom tables:
| • | Perform the Powertrain On-Board Diagnostic (OBD) System Check
and verify all of the following items: |
| - | The powertrain control module (PCM) and the malfunction indicator
lamp (MIL) are operating correctly. |
| - | There are no DTCs stored. |
| • | Verify the customer complaint. |
| • | Perform the visual and physical checks. |
Locate the correct symptom in the list at the end of this section. Follow
the procedures in the appropriate diagnostic table. If the problem can not
be duplicated, refer to
Intermittent Conditions
.
Visual/Physical Check
Notice: Use the connector test adapter kit J 35616-A for any test that
requires probing the following items:
| • | The PCM harness connectors |
| • | The electrical center fuse/relay cavities |
| • | The component terminals |
| • | The component harness connector |
Several of the symptom procedures
call for a careful visual and physical inspection. This can lead to correcting
a problem without further checks and can save valuable time. This
check should include the following areas:
| • | Verify that the PCM grounds are clean, tight, and in the correct
locations. |
| • | Inspect the vacuum hoses for splits, kinks, and correct connections,
as shown on the Vehicle Emission Control Information label. Check thoroughly
for any type of leak or restriction. |
| • | Check the air intake ducts for collapsed or damaged areas, especially
between the mass air flow (MAF) sensor and the throttle body. |
| • | Check for air leaks at the throttle body mounting area, the
MAF sensor, and the intake manifold sealing surfaces. |
| • | Inspect the wiring harness for poor connections, pinches, cuts,
or other damage. |
| • | Check for loose, damaged, or missing sensors and components. |
The following Symptom tables are located in this section:
