Ok, I just went on a 5000k trip and on the way back my truck (2001 F350 7.3) started doing the weirdest things. First the turbo kept blowing off pressure at much lower RMS than it should (BTW I was towing about 6k and had a camper on it) usually about 2000 RPM or so. it normally doesn't blow off until around 2600-2800 RPM with a load. So it became almost impossible to do more than about 30k up standard hills I should fly up. I pulled over at the side of the road and checked for codes, I had a code saying that the Barometric sensor had a problem, and I had a code that said that my turbo pressure sensor was having probs. I cleared the codes and returned all programming to stock. All was fine for about 10min when it began to progress again from slight problems to the point at witch I couldn't even drive up a hill. Cleared codes again and all as good for a while.
After reading online through this process I found something that said to disconnect the MAP sensor if these codes were coming up, I did so and the truck ran like it was brand new again. (BTW Disconnecting the MAP sensor is the only thing in this whole process that gave me the check engine light in the dash.) I drove for quite some time, satified that the MAP sensor was the problem until the truck began to miss and run like a bag of crap. I was now unable to even go faster than about 30k on straight roads.
I hooked the MAP back up and pulled more codes, now the codes were telling me that I had an "OPEN CYL 7 Circuit" and a few other major weird ones that I can't think of right now. I cleared them and that didn't fix the problem.
After letting the truck sit for about 10min all was good again. Then after driving for the ferry it acted up again. Getting progressivly worse.
I got on the ferry (FINALLY) and let the truck sit. 1.5hours later I leave the ferry and all is fine and no problems now. Now that I am in my own town I figured I would TRY to make it happen again, so I shift @ 2500RPM and work the truck a little to try to heat it up so to speak. And the turbo begins to blow off pressure early again @ about 2000rpm and the lack of power and trubo problems return, but no codes now. I removed camper and trailer and now I can't even make it return by beating on it.
It appears that this problem is somehow HEAT related maybe? My truck requires a major LOAD to make this happen... And to top it off now, I can't even get my SUPERCHIPS programmer to turn on when I plug it into the truck now...
Anyone please have any ideas???? HELP! I don't want to replace all kinds of crap pointlessly... Can I test any sensors such as my turbo pressure sensor with a multi-meter?

Thanks,

 

Hmmm. If you are home now, somewhere in Canada as I assume 30K is metric, then I would disconnect both batteries and go to bed. Then I would start fresh in the morning and see if the tuner will work.

Have you checked with Superchips on this? I have no experience with a tuner. I don't really think I want any but maybe someone else will chime in.

 

Is your chip loose? A bad connection from a chip can cause all sorts of issues. Maybe pull it out and clean all the contacts really well.

 

don't know about the rest of it but check cigerette lighter fuse to get programmer to work

 

Tuner goes through OBD connector doesn't it? Fuse #30 or something like that, I have not checked but same as cigar lighter like rbaker stated IIANM.

 

Ok, that fixes the tuner problem... I blew my CIG lighter fuse the other day... Thanks for that guys... how about the other issues? Anyone got any ideas???

 

When you refer to the "CHIP" are you talking about my programmer? (its external and only gets connected when you program it... If not that are you talking about the PCM? I have not checked that yet, I understand that its like a 10mm socket to disconnect the harness from it and check for a bad connection. But if it was this, how would the turning the truck off and letting it sit for a while delay the return of the turbo blow off issue? (I am only assuming that this is what it is as it sounded like it and after a while you can't even here the turbo spin up anymore and it lacks the power that the turbo would normally make for you.

 

Sorry, I don't have enough experience with all the chips & tuners cuz I don't use them. If you replaced the blown fuse, did you try returning the program back to stock to see if that solved your problem? Altering the PCM with either a chip or tuner could cause an issue and it's best to diagnose your problem with these possibilities ruled out.

 

I haven't replaced the fuse to determine if my tuner works again yet, however that is very likely the reason it won't turn on anymore as I blew the fuse the other day. When the problem first started, I returned my truck back to stock to see if my tuning was the problem... And the problem persisted. I am now only using the tuner to read the codes until I have the situation rectified...