Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Vehicle shuts off after 45 minutes of running, whether running or idling. Like if turning the key off. Then, have to wait about half an hour or so for it to start again. The problem just keeps repeating. Have already replaced a few items like, first gave it a tune-up, 2 bad injectors, one coil, alternator, all related relays, ECM. Even took the central junction box apart, cleaned it out and put it back together. Tested fuel system, good. What I didn't do was replace the diode that's soldered in the printed ckt of the CJB. The veh. is a 2003 Ford Expedition 5.4L Eddie Bauer 2 whl dr with 146k miles.
The first thing you need to do is figure out what is missing when it won't run. Make sure that your coils and injectors are firing. Do you have an RPM signal when cranking?
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