RICOCHET - I would suspect the IAC at this point - You really have to clean them good - I use carb/brake cleaner , don't let it soak, it may ruin it. Spray it into the IAC then use compressed air to clean it. Do that a two or three times then use WD-40 - Fill the cavity and work the spring Mechanism with a small screw driver back and forth for awhile.

Take a small flashlight and zone in on the mechanism and check for small black carbon deposits , this is what causes it to function improperly , try to chip those off carefully , lube it up good and use compressed air again to loosen even more. Re-install.

I would pull the TB as well to double check the ports - make sure your EGR port and others are clear - that EGR has been known to almost clog completely. You really can't trust anyone to do that but yourself - the dealership will run a service thru it usually , but won't dismantle. Depending on the tech of course , they may throw parts at it that could end up quite costly, leaving you with the same problem now or in the near to immediate future..

 

Vehicle listed with 120k. stuble under hwy load, nail the throttle gets better for a while. Threw in some inj. cleaner wife says its a little better. Changing the filter this week end. Hope all is good, I hope its not a COP. Also fuel economy blows in her truck. I have a 99 with a trashed transmission that gets about 4-5 mpg better.
Lowflyingbird

 

jbrew, thanks, I'm going to eventually go into the TB and do the other cleaning and checks you suggest because to me it sounds like something along those lines especially with it only occuring at idle and only when warm. It just ticks me off that I suggest to the mechanic those same items and he says that he's done them. One never knows. Anyone want to add credence to the reflash argument?

Thanks again,

ricochet