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Junior Member
78 Posts
Discussion Starter #1


So this has been going on now for almost a year and it is driving me crazy.

I have a 2003 f-250 4x4 with a 7.3 automatic.

Driving down the road at any speed or even sometimes while idling, truck just shuts off... the tach and all gauges shut down..
Usually just for a few (maybe 5 seconds), then automatically just comes right back on. sometimes I will have to put it into neutral and key start it.
It absolutely does not matter how warm or cold the vehicle is or outside temps are.

It is not the CPS (New Ford)
It is not the IPR (New Ford)
It is not UVCH (New Ford)
It is not the IDM (New Ford)
It is not the PCM (I have tried 3 known good ones)
All fuses and relays are working.
Cigarette lighter is working.

I removed the aftermarket Remote start and alarm system thinking it might have been that, considering that I had already had issues with the remote start system giving me troubles about a year ago.

While under the dash, I repaired all of the wiring where a** Ho*** used scotch locks while installing such alarm /remote start system...

All wiring under dash cleaned up and back together and thought it would be solved because I found lose connections at the scotch locks, but driving to work today it happened again..

Also, another note about this,,,,, Everytime I plug in a code reader or scan tool to my OBD2 port it does not find my PCM or Chip.

(it does not matter weather or not I remove my chip from the processor either)
I am at a major loss here trying to figure this out... I have checked out the harnesses under the hood as best as I can. no bare or chaffed wiring that I can see.
The major part of all of this is that a couple of times the truck wouldn't start back up. It would just crank and crank with not even trying to fire at all. Then miraculously after a couple of days it fired up.

I want my reliable truck back...

Please, if anybody had a known good answer for this, other than it's a FORD please help out if you can...

Old Fart
889 Posts
These trucks can create quite the wiring challenge. I was blowing out fuses in the tail light circuit. I did pretty much what you have done, but did not replace items like the ICP or the PCM. I crawled under the truck and was looking for bite marks on the wiring harnesses. I removed everything I had added to the electrical circuits. Then I started to go through every light in the truck. I started with the taillights and moved forward. I finally found a shorted light bulb in the cab lights that was causing the fuse to blow. I had never seen a light bulb short out and I am 66 years old and have been wrenching on cars/trucks since I was 12 years old.

I wish I had a cure for you or even an educated guess. Good luck and keep at it!

Senior Member
3,051 Posts
Just a guess, but check the ignition switch and steering column wiring. These are a high wear item and can do funny things intermittently.


Junior Member
9 Posts
I had the exact same problem. Just never knew when it would happen.

In my case, the problem was the harnesses leading to the fuse holder next to the steering column. There were a couple of terminals that were not tight so I pulled a bunch a wires and re-crimped them. This happened back in 2003 when I bought the truck. I found out through a friend that knew the previous owner that he decided to sell the truck for that specific reason after a number of trips to the dealer without any luck.

How I found the problem? I was removing some wires near the brake pedal while the listening to the radio (ignition switch in accessory) when I accidentally touched the wires behind the fuses and all power went out. Power came back after wiggling the wires I knew the problem was there.

harry6.0 mentioned the wire and the switch. I ended up repairing that wire too. I am not sure if the two were related or not.
Good luck!!
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