Thanks guys for all the suggestions. The good/bad news is that replacing the IAC valve helped quite a bit (the RPM doesn't dip as low) but it's still dipping down when going to reverse or when stopping. And yes I did clear out the PCM memory before starting up the truck.

I'll drive more the next few days to get a better feel as I only got to drive it 6 miles yesterday; it hasn't stalled yet which is a nice improvement.

Possible fixes I'm hoping is to replace the TPS sensor, or reprogram the PCM.

The battery is less than a year old, I replaced it around Dec. as it was corroding.

 

Thanks for that info! You have just confirmed that at least my 4.7 idles at the same range.

 

Drove it a bit more this morning. So far there is a huge improvement however the issue isn't completely gone, the idle still wavers a lot when stopping or going in reverse. Next stop is to order a new TPS.

 

every once in a while when i come to a stop, my idle will dip into the 400 rpm range. it sounds like mine is taking the same path as yours, as in it almost dies. the cool thing is when its idling at 425ish, it sounds cool as hell, sounds like it has a huge cam in it.

 

well i had somewhat same problem. 2000 dakota 4x4 5speed 4.7 v8. everytime i would stop it would die. no check engine light until later. but when i replaced 2 oxy sensors it still didnt help and finaly the last one replaced finally helped it out. i had to replace the speed sensor on the rear diff.it would always die when slowing down or when i turned the steering wheel.hope this helps you out.

 

problem cleared up in 5 mins with new speed sensor..see if thats works. only $35

 

Thanks. I'll keep that in mind. My truck stalled out yesterday again but it was the first time in a few days.

The TPS comes in next week so I'll replace that and see what happens.

 

Installed the new TPS and there is no change with the issue.

I've added two videos to youtube for people to see what the issue is like:

http://www.youtube.com/watch?v=7B4NtPIRw2g
http://www.youtube.com/watch?v=x6WP_-qvha8

In these videos I jam the RPM decently high, then come to a complete stop suddenly. Where you see the drop is actually when the car has that snap back effect when stopping quickly. Hopefully this insight will give new ideas to solve this issue.

Deciding what to do next...

 

Did you reset the PCM?

 

I did for the IAC, haven't done it yet for the PCM. Will reset it and try again.