Hi, friend brought me his 2001 F250 SD 7.3 to see if I can figure out what is wrong with it. He has had it to several shops to no avail. It started with lights coming on and off periodically and ended with starters burning up on a regular basis. 3 or 4 by now. It will roll over on it's own and do all kinds of crazy stuff. Shops have pretty much stuck with swapping starters and solenoids but I don't think that is it. I have pulled the main fuse block under the hood and it is clean, next the one under the dash. I can't see moisture in the GEM but there was moisture on the outside of the box. The GEM looks OK but that doesn't really mean anything. I put a Ford scanner on it (AutoEnguity type) and it scanned and brought uo several GEM failures but not sure if that is from hooking and unhooking stuff. I have had to keep bat cables unhooked as I am afraid it will burn up when no one around. When I scanned I had to hook up batteries and when I turned on the ignition it went crazy with flashing lights and relays clicking from behind the dash. I cleared the codes and it stopped. GEM? Can GEM's be tested? I know they can be re programmed so why not tested?

 

It sounds like the Gem module is the culprit. Moisture on the outside means water is Getting in the cab and effecting it. Is there a tuner on the truck by chance?

 

No, no tuner involved in the death of this Ford

 

Does anyone have a part number for this or are they truck specific

 

Could it be a wiring harness short ?
on our early diesel there were real concerns about the way the wiring harness stretched around the engine and caused some grounding...
wondering if it could be the same on this 7.3 ?

good luck !