Visual/Physical Check

A careful visual and physical underhood inspection must he performed as part of any diagnostic procedure or in finding the cause of a failure. This can often lead to fixing a problem without further steps. Inspect all vacuum hoses for correct routing, pinches, cuts or disconnects. Inspect all wires in the engine compartment for proper connections, burned or chafed spots, pinched wires, contact with sharp edges or the hot exhaust manifold. This visual/physical inspection is very important. It must be done carefully and thoroughly.

The importance of the visual inspection cannot be overstressed. Visual inspection can lead to correcting a problem without further testing and can save valuable time. The check should include:
^ Use of aftermarket equipment (e.g., alarm systems, cellular phones, lighting, CB radio, etc.).
^ Use of aftermarket parts (e.g., air filter, PCV valve, spark plugs, fuel filter, battery, etc.).
^ Inspect wiring harnesses for proper routing, connections, pinches, chaffing and cuts.
^ Inspect PCM and component grounds for tightness and evidence of corrosion.