ok we have gotten the windstar on and we think all the problems fixed so went to drive it around and when he went to wot it wouldnt shift. then when we got home it was idled up to 2k just sitting there. when we gave it gas and let off it is back firing like crazy what could it be.

 

flip the iac around

 

did that
he broke down and went and got a brand new tps and now it is running like a champ!

 

is this the one that wasn't idling correctly.
so it was the tps. at least it's running

 

yea same one....it all lead back tou the tps i took it off and the piece inside would spin freely and the new one didnt so that is what it was....Not more off idle or backfiring,and it shifts now so.