I'm really hoping that y'all can help me out. I've been battling a electrical problem for month. First off I have a 2001 F250 7.3. 206,000 miles. DP Tuner. Over the past eight or so month when the truck would come to a stop it would then try and start in 3rd gear and if not caught just died. Have to restart the truck. Put her in 1st and take off and shift from there. Also when the cruse was set. I would set on the break. The truck would shift hard and while I had my foot on the break. The radio would shut off and come back on. All the lights on the dash would come on and the spedo and tack would go up and down. We thought we traced it to the GEM. Replace the GEM and the fuse box that goes with it because we found evidence some rust under the dash and thought that was with issue. The GEM was replaced last week. Truck was running fine until today. First off I noticed that when I stopped and put the truck in gear the RMP of the motor would rev up and also indicated on the tach. The I tried to take off after putting her in gear and the truck just died. Started it back up and headed home. While on the interstate with cruise set. As soon as I turned on the blinker to change lanes. The cruse was disengaged. The speedo and tach went nuts and I thought the truck shut itself off and came back on again.
Can someone please point me in the right direction of where to look next or what to test or replace? I've spent a lot of money so far but I need it fix and need my truck back for my business. The person that's been looking at the truck so far is very familiar with 7.3 because he's had several himself and owns his own shop. Any help would be very much appreciated. I don't know where to go from here. I can answer any questions that you might have. Thank you.

 

i would pull the tunes and return the truck to a stock running condition and see what happens.

 

I'll give that a try and see what happens. My 7.3 guy doesn't think it's the tuner. It's the tuner that came off of his truck. Any other suggestions?

 

Yea, Do both of the PCM Code numbers match?

 

How do I check to see if the PCM numbers match? I had a ford dealership flash the new gem and the new gem came from them. Have them my VIN when we ordered it.

 

i dont have dp tunes but i looked into them a while back and if i remember correctly they ask for your pcm #'s to burn your tunes. so if the other truck had a diffirent pcm # than yours. it could be set up diffirent . you may need to get it reburned. see how it does with out the tunes. you will see the #'s on the side of the pcm when you pull your chip out. write them down for later.

 

Sounds like the torque converter isn't unlocking. Not sure if the brake light switch has anything to do with it or not. Somone higher up may be able to chime in.

 

Here you go.
https://dp-tuner.com/skin/frontend/d...r-pcm-code.pdf

 

You have two dates here. When did you put the chip in? Did your 7.3L guy compare PCM codes and transmissions... or does he by chance have a manual? Does he have any other mods?

 

The codes match. When I got the chip from my friend. I called the guy at DP Tuner. I then sent him the chip. Gave him the PCM code off my computer. He reprogramed the chip and then sent it back to me.

 

I don't see a "when" on the chip install. The chip controls the transmission over the PCM. When things get weird, it's always best to pull the chip. I'm not saying the chip has a flaw, but sometimes the connection is part of the problem. Troubleshooting should always be done with a stock truck, because it has the fewest unknowns.

 

I wanted to thank everyone that replied and all of the other posts that have been put up here. Finally got the problem fixed. Y'all have been more than helpful and I know I'll be back to read the knowledge that y'all have about the 7.3. I want to keep it around as long as I can you y'all will be helping with that. The problem was a bad alternator that would fail and not put out the voltage when it was put under a load. This has been going on for a very long time. It was complicated by a bad ground on the passenger battery. That caused the Body Control Module or GEM module to fail. Everything has been fix and I'm back up and running. Thanks again.

 

Update on my stall issue.

Well, since I got the truck back from the body shop, it hasn't stalled. I'm retired so I don't drive the 60 miles round trip to work anymore. Anyway, I'm sure it's not fixed, like I said, it may not stall for a month, or may stall 6 times tomorrow. 🤷‍♂️

The paint was so embarrassing, I hadn't cleaned the interior for about 7 years. The truck mostly went to the dump and back. At the body shop and removing front and rear glass the interior had a lot of BS sanding dust. I had a detailer work on the truck, just an exterior wash and full interior detail. He spent 6 hours on it.

I got my old pride back in the truck. Kid did a bang up job. So until it stalls, I'm just working on little issues. Had to install pig tails for the door panel courtesy lights.

 

Erhm..were you originally JazzVT321?

 

No, I may have been om this sight before, but it didn't recognize my email address that I've had since the 90s, and not a user name I'd use. Not a jazz fan.