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Any suggestions ...? Scrapping the truck comes to mind ... Seriously though, I would really appreciate some help with this. It's a very nice old truck, with new built up tranny, and only a few thousand miles on a new motor from Asheville engine co. Something happened after a ground wire was inadvertently piched between the engine and transmission. This caused ignition module to fry twice, so the diagnostis began. Eventually this issue was found and rectified, but a new problem had already been created. The computer keeps resetting upon acceleration (intermittent problem). After testing every sensor, all of the 5v reference signals etc (including replacing the entire pedal assembly, although the sensor tested as good), the computer was replaced, and the core sent out. The company called to say that there was absolutely nothing wrong with the core they received. The fuse panel board has replaced, along with most of the trucks wiring harness. Using the same software that ford uses, nothing was found to solve the problem for a 30 year ASE certified mechanic/ 20 year certified diesel mechanic.
The following is a text from the mechanic:
I've already removed it (aftermarket alarm system). I removed all aftermarket plugs and harnesses. I have literally ruled out every electrical component however I'm systematically going over everything again one at a time. I've got my Ford IDS program on it and my Snapon Modis Ultra along with Genisys evo and they are all telling me the same thing. All PIDs are normal except the "time since start" and "after start timer" are resetting along with the WTS light which tells me electrical. Like I'm turning the ign off or disconnecting the batteries. I've got that friend of mine (ford certified powerstroke technician, works for a large ford dealership) coming over tomorow to look with fresh eyes. Today I've removed the current flashed program on the pcm and reflashing with the latest flash. It has the current flash when I replaced it but the one I'm doing now literally builds its own flash file one pid at a time. This way it's correctly formatting for the aftermarket turbo and injectors instead of relying on the piggyback "livewire".
 

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Typically in a situation like this I would be looking for power and ground issues at the PCM. Also there are at least two VPWR circuits that feed the output devices which if shorted, even momentarily, will shut off the PCM. A shorted injector or fuel injection harness can do the same. Can be a beyoch to find but ohhh sooo satisfying when you do. I love these jobs; it's all about the hunt for me! Good Luck!
 

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What year truck is this? First off a pinched ground wire shouldnt short out a pcm. You have not described the problem other than stating the computer resets whatever that means.
 

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Typically in a situation like this I would be looking for power and ground issues at the PCM. Also there are at least two VPWR circuits that feed the output devices which if shorted, even momentarily, will shut off the PCM. A shorted injector or fuel injection harness can do the same. Can be a beyoch to find but ohhh sooo satisfying when you do. I love these jobs; it's all about the hunt for me! Good Luck!
Keith, could you add some more detail on the circuits that feed output devices that could shut off the PCM?

Fan clutch, GPCM? Others like EGR, or IPR? Is it the F2.22 circuit or are there others?
 

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Any suggestions ...? Scrapping the truck comes to mind ... Seriously though, I would really appreciate some help with this. It's a very nice old truck, with new built up tranny, and only a few thousand miles on a new motor from Asheville engine co. Something happened after a ground wire was inadvertently piched between the engine and transmission. This caused ignition module to fry twice, so the diagnostis began. Eventually this issue was found and rectified, but a new problem had already been created. The computer keeps resetting upon acceleration (intermittent problem). After testing every sensor, all of the 5v reference signals etc (including replacing the entire pedal assembly, although the sensor tested as good), the computer was replaced, and the core sent out. The company called to say that there was absolutely nothing wrong with the core they received. The fuse panel board has replaced, along with most of the trucks wiring harness. Using the same software that ford uses, nothing was found to solve the problem for a 30 year ASE certified mechanic/ 20 year certified diesel mechanic.
The following is a text from the mechanic:
I've already removed it (aftermarket alarm system). I removed all aftermarket plugs and harnesses. I have literally ruled out every electrical component however I'm systematically going over everything again one at a time. I've got my Ford IDS program on it and my Snapon Modis Ultra along with Genisys evo and they are all telling me the same thing. All PIDs are normal except the "time since start" and "after start timer" are resetting along with the WTS light which tells me electrical. Like I'm turning the ign off or disconnecting the batteries. I've got that friend of mine (ford certified powerstroke technician, works for a large ford dealership) coming over tomorow to look with fresh eyes. Today I've removed the current flashed program on the pcm and reflashing with the latest flash. It has the current flash when I replaced it but the one I'm doing now literally builds its own flash file one pid at a time. This way it's correctly formatting for the aftermarket turbo and injectors instead of relying on the piggyback "livewire".
Oh man I feel you I’ve got a 2006 F-250 diesel with that same issue only it throws my truck into limp mode a 5 gallon gas can and a match comes to mind often lol haha haha so I’m stumped as well I sorry I can’t add a remedy peace everyone
 
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