High Idle Help

My 1986 Ford F150 is Idling too high and dont know why i have replace plenum gasket, throttle body gasket, cleaned IAC Control valve checked egr and still have a high idle and dont know why

PLEASE HELP
Thanks

Check all your vacuum lines for leaks. They can be hard and cracked or soft/gummy and not sealing properly. You can alos try around the intake manifold with carb cleaner or a mech's stethascope.
Good hunting.

does it have a carb. or is it fuel injected? if it has a carb. then you can try adjusting it your self(if you trust your self, the carb. is sooo touchy. i wouldnt even trust my self.) if you dont trust your self take it to a shop, but that shop may have you go somewhere that only works on carbs. if it is fuel injected then all i can think of is adjusting your throttle body if it is even possible.(i dont know, i dont have much experienxe with fords, just got a '93 F-150 about a week ago. before that i was driving a '93 Olds Achieva. so i know A LOT about those. and i know that there was noting i could do to adjust the idle)