Intermittent Problem Diagnosis

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.

Intermittent fault testing requires duplicating circuit or component failure to identify the problem. These procedures may lead to PCM setting a DTC which may help in diagnosis. To reproduce conditions creating an intermittent fault, use the following methods:

Lightly vibrate component.
Heat component.
Wiggle or bend wiring harness.
Spray component with water.
Remove/apply vacuum source.

Monitor circuit/component voltage or resistance while simulating intermittent. If engine is running, monitor for self-diagnostic DTCs. See QUICK TEST in SELF-DIAGNOSTICS - 7.3L DIESEL article. Use test results to identify a faulty component or circuit.