On the block it say's 4.8-5.3 the vin from the truck says 5.3? The TB is off my 4.8 The 04 truck was fly by wire and my truck is cable.

 

Is the tune set up for a cable TB or electronic TB?

 

Should be cable. Put in a stock PCM tuned to my vin and the idle was still at 2000

 

Maybe your tachometer is broken. :nunchuk1:

 

Nope checked it with a tek2. The tek2 says the pcm is calling for it to be at 600 but it is still at 2000. I can put my finger over the iac hole and get the idle down and even kill the motor but let the iac do it at is stays at 2000.

 

I wasn't serious about the tach comment. Just trying to keep things light.

You need to find your vacuum leak. If you've tried several pcm's and several throttle bodies/IAC's, then it isn't the tune, or the IAC. The IAC just does what it's told to do by the pcm.

The only thing that can cause what you are describing is un-metered air entering the engine. Check your pcv system, brake booster, air intake tubing, hoses, etc. until you find it. You are overlooking something simple, and you'll probably laugh for an hour once you find it.

Good luck with the search.

 

Pulled all the lines off plugged them did not help pulled them off at the intake and plugged them no help. Next week I am going to pull the blower back off and see if I can find anything wrong with the intake even a small scratch.

 

Are you still running an EGR valve?

 

Nope the truck never had one

 

You got the supercharger used, right? Previous owner may have had EGR, removed the tubing, and not plugged the hole.

I'm grasping at straws to try to help you here.