4-1
Troubleshooting
4.1 Vehicle Inspection
Many problems can be found by performing a visual and “hands-on”
under-the-hood inspection before starting any diagnostic procedure.
•
Has the vehicle been serviced recently?
Sometimes things are reconnected in the
wrong place, or not at all.
•
Do not take shortcuts. Inspect hoses and
wiring which may be difficult to see because
of location (under air cleaner housing,
alternators and similar components).
•
Inspect the air cleaner and ductwork for
defects.
•
Check sensors and actuators for
damage.
•
Inspect all vacuum hoses for:
- Correct routing. Refer to vehicle
service manual, or Vehicle Emission
Control Information (VECI) decal
located in the engine compartment.
- Pinches and kinks.
- Splits, cuts or breaks.
•
Inspect electrical wiring for:
- Damaged insulation caused by sharp
objects (a common problem) or by hot
surfaces such as engine and exhaust
manifold.
- Corroded and broken wires.
Section 4
Troubleshoo
ting