Since you said it was an aftermarket CPS, I am still betting on that is the problem. The Borg Warner has been reported to do this and I tried a "Standard" brand unit that would cut out in the rain. I could turn on the windshield wipers when it was dry out with no problems so I thought I was good. But the first rain that came, it started to cut out while driving. This is a pretty common thing with the aftermarket CPS units for some reason. I would get a factory unit and put it in before you spend to much time chasing down other things.

Some people are running the CPS from the earlier OBS trucks with good results or you can just get the Grey CPS that Ford will sell you for your truck. The Grey unit is said to not just completely die if it goes out and will put the truck into a limp mode. The original Black CPS would just go out and the truck would die.

94-96 (DU-87) CPS = F4TZ-12K073-C
97-03 CPS = F7TZ-12K073-B

 

Yeah, it was CPS problems all along in the end.

He actually got 4 or 5 bad new CPS's in a row from two different sources. I don't know what the odds are on that, but a lottery win can't be far behind.

Finally installed a CPS that actually worked and no more problems. The truck is still running great for it's current owner.

 

That is funny, I didn't even look at the dates and didn't realize dholland dug up an old thread.
Well it is good to know that I was on the right track anyway. Some of this info never changes.

 

I find it hard to believe that that many CPS's were 'bad'. I had the same issue 'when it rained'. I also changed out the my CPS. It turned out m,y electrical plug needed some sealant to keep the moisture out. I believe that it is/was the moisture that was killing it and that he finally got a good seal on it.

imo

 

I don't know what to tell you, I can only pass on the info as I have it. The mechanic/shop had a lot of time and their own money into the repair and supposedly verified that the CPS's were bad. I have no reason whatsoever to think they were lying about it.

I guess you're free to draw whatever conclusions you like though.

 

I have 2000 7.3 Power Stroke I had same problem in wet weather replaced CPS from ford..... magically, problem is gone been working on this problem 2 years Thank you X 100