Justin,
Year? Mileage? Is it a 7.3?
I know a fair bit on the 7.3's. You have seen mine. Below is about the 7.3's.
The High Pressure Oil Pump (HPOP) is what powers the hydraulic side of the injector., The HPOP is hydraulically powered by your engine oil. Has the oil been maintained properly for the life of the engine? The injectors also have an electric side that has to be fired as well. The IDM (injector driver module) fires that. It is over 100 volts DC. It will shock the piss out of you. Be careful if you mess with it. Also, the cam position sensor had a recall. My truck wouldn't run at all when it malfuctioned. But, there was one time when it would stumble around and barely run. That fixed it that time. There is a wiring bulkhead in the valve cover gaskets. The glow plug and IDM circuits run through there. The locking clip inside the valve cover will get weak over time and the vibration of the engine will slide the plug under the valve cover out. If only one side of the engine is firing, that may be why only ether will keep it running.
I kept trying to start mine when the plug under the valve cover came out. The IDM has so much voltage on it that it will arc onto the head. About 3 of those and it fries. They are about $700 new. I found a used one online.
Hope this helps. You can find a lot of info at
www.dieselstop.com. It's a tech bulletin board for nothing but the best towing, best looking, strongest, has to wait on chevy's and dodge's all the time FORD TRUCK!!
PM me if you have any questions.
