I just replaced my IDM due it getting flooded and now my truck runs and drives, but when accelerating going past 1500rpm it starts stuttering. I plugged in my scanner and it cannot communicate with the PCM but can communicate with the other computers. Check power and ground to the PCM and they are good.

It was communicating before the IDM was replaced and that's how I found out the IDM went bad.


The PCM number.
- PTM2 DPC-422

 

If the truck starts and runs, then the PCM is communicating with the IDM. There are only 3 modules in our era trucks. PCM, IDM and VSM or GEM based on the model year.

Did the truck flood or just the IDM?

 

Just the IDM

 

I would unplug the PCM, and spray the connectors with CRC contact cleaner, you can find it at any box store, auto store...
several different flavors of it

spray, plug / unplug / plug it in / pull and put it back together.

 

Tryied that, didnt seem to work. Still getting the code

 

Just the IDM was flooded

 

Have you checked your fuses?

 

Yes I have checked all my fuses and relays

 

What code (specifically, by the DTC number) did you pull... that inspired you to change your IDM?

 

Had no communication to the IDM and it had water inside. At the same time i put new motorcraft ICP, IPR, and cam sensors in.

 

How does the fuel filter look? Any chance of getting fuel pressure when the stuttering starts?

 

It has a new fuel filter and fuel pump, Having no issues starting it.

 

Where'd the IDM come from? Might be no good.

 

GB Remanufacturing

 

If you're stuttering and stammering above 1500 rpm then you need to test the fuel pressure. There is a simple method in the tech section explaining what you need and how to do it. You'll want to check the fuel for aeration too. You can do that by catching a sample of fuel from your test rig before installing the gauge. If you get bubbles in your sample then you've got a leak somewhere letting the pump suck air. If you've checked all the fuses with a meter not just visual and they all are good you might try a hard reset on the PCM. It's kinda a long shot but I've gotten lucky and cured weird behavior with it before.