Visual and Physical Underhood Inspection

One of the most important tests is a visual/physical underhood inspection. This can often fix a problem. These quick tests take only a few minutes, can save valuable time, and help you correct the problem. For further information, refer to Visual/Physical Check in Symptoms. Initial Inspection and Diagnostic Overview

All Powertrain diagnosis should begin with a thorough visual inspection. Visual inspection can often lead to repair of a simple problem without use of the tables.
^ Inspect all vacuum hoses for being pinched, cut, disconnected or misrouted. The EVAP Purge Solenoid vacuum hoses can easily be installed incorrectly. Be sure to inspect hoses that are difficult to see such as beneath the upper intake, generator, etc.
^ Inspect for proper ground connections, ground eyelets connected to ground points, star washers installed, if applicable.
^ Inspect the battery positive junction block for loose retainer nuts.
^ Inspect other wiring in the engine compartment for good connections, burned or chaffed spots, pinched wires or harness contact with sharp edges or hot exhaust manifolds.
^ Inspect for blown or missing fuses and for relays missing or installed in the wrong locations.

Refer to Power and Grounding Components in Diagrams.