I have 94 F150 and it idles way too fast about 2000 rpm.I replaced the iac valve and it worked for a while but now back to the same problem.Also when it is idling to fast it dont shift right wont come out of first gear.When i unhook the iac it shifts fine (sometimes)but engine stalls and dies on me.I need help with this problem as i am getting ready to sell this truck and thats the only nagging problem i have with this truck.

 

Sounds like the upper plenum gaskets are blown out. Take a flashlight and look down theinside of the upper plenium, your looking for gasket material sticking out, about halfway down the plenium. [sm=mail.gif]