ok ive read everything on this subject and done everything short of changing to maf, so no vacume leek new tps aic egr, coolent temp sencer is fine changed pvc valve and screen. but randomly it will idol to about 2k if not 25k so but when i turn the car off there is a huge gasp of air releasing when i do so??? any ideas ive tried everything!!!!!! 88 mustang 5.0 ho by the way stock excpt bolt on.

 

reset base idle? check act maybe clean it off?

 

act? and i ould reset my base idol but it olny happens randomly when the car can heat up and cool down in the process of driving. so wile im driving it happens. half the time if i restart my car it stops but its kinda like somthings stuck open????? loud gasping air from the intake what would that be?