Posting for a buddy.
He has my old 94 PSD and he put a bully dog 6 pos. chip in it. When its cold he lets it idle for a few minutes then turns it to the high idle. It idles up like it should then after a few minutes it hits about 1500 RPM and then dies, but it will restart normally. Any ideas what would cause this?

 

could be the ipr or icp. did the check engine light come on?

 

Ok. Next time i'm out there I'll get my scanner on it. He didn't say if it did or not, but the trans just went out so he won't be driving it for a bit.

 

one thing you can do is check the icp sensor to see if there is oil inside. make sure your hands are extremely clean, if there is any oil inside it will screw with the icp

 

Ok, I'll let him know.