Injector / IDM Drama (nightmare)

[aocabrown]

I have a 2001 CC with 200k miles.

My truck ran 'ok' until last week. Took in for diag because I thought I had at least one poor injector (and noisy)...#8...and want to get it right before installing Jody's DP-Tuner chip. To make a long story short...I had them replace all 4 on that side while they were in there (not my best decision). CCT and other diags afterward showed some issues, even with injectors that had not shown poor before and/or were just replaced with new ones. They put a new UVC harness on (only on drivers side they were in) and re-tested...same results. Said IDM was bad or going bad.

ANyway....truck ran fine for 20 miles. Upon all future cold cranks, terrible idle and terrible performance (30-40 mph max). But....on every cold start..after about 20 minutes of driving, truck straightens out and runs 'almost' nor.mal. Still has a noticable miss and still chugs up small inclines (original issues). On small occassions, it actually feels like it runs on all cylinders and has decent power.

This last test today showed faulty PCM not the IDM. They said I have a likely electrical issue causing the various codes and erradic performance. They also said the ODB port didn't have any power until they 'jiggled' the fuse box.

So now the question....how to find the issue? Thoughts?

[powerplant]

Do you no what the codes were mine had same problems and the IDM was bad. If it is your idm dont buy it off the stealership they want 975.00 bought mine off of IH.

[aocabrown]

Originally Posted by powerplant

Do you no what the codes were mine had same problems and the IDM was bad. If it is your idm dont buy it off the stealership they want 975.00 bought mine off of IH.

I believe P1294 was one of them. one was for IDM and one was for something related. Don't have them in front of me.

I'm investigating valve cover wiring connections (outside cover) today. I was thinking of getting the IDM online ($150-$300) depending on age and source. My only question....how the heck do you get to it? did you do yours? how long did it take? anything to do to IDM other than plug it in?

THANKS

[powerplant]

early 99 is behind iner finder well drivers side on fire wall. one bolt bracket plug in bolt up and start.Herd the ones off e-bay are junk.

[powerplant]

Did uyou get it figured out.

[Hoytster]

Hey AOCABROWN, if you do need an IDM let me know. I have a rebuilt unit that was never installed I'll ship to ya for $150.

[lilredpowerstroke]

Mine did kinda the same thing but ended up being a short in the main wiring harness.

[mschn99]

check the harness right where the bulkhead connector goes over the drivers side valve cover. Disconnect the bulkhead and look at the wires and see if any have rubbed through the insulation while rubbing on the valve cover...