Diagnostic Aids

The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 20 percent. This is referred to as the rest position. The throttle valve should not be completely closed nor should it be open any more than the specified amount. The throttle valve should move open and to the closed position without binding under the normal spring pressure. The throttle should NOT be free to move open or closed WITHOUT spring pressure. Replace the throttle body if any of these conditions are found.

IMPORTANT: Operating the throttle blade with the Throttle Blade Control function of the scan tool may cause additional DTCs to set. Do not attempt to diagnose DTCs set during this function.

The scan tool has the ability to operate the throttle control system using Special Functions. Actuate the throttle valve using the throttle blade control function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly.

Check for the following conditions:

Use the J 35616 Connector Test Adapter Kit for any test that requires probing the PCM harness connector or a component harness connector. See Special Tools .
Poor connections at the PCM or at the component-Inspect the harness connectors for a poor terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections for the proper procedure.
For intermittent conditions, refer to Intermittent Conditions .