Interesting ill check it thanks

 

did you ever find the fix to your high idle situation. I'm currently dealing with what I feel is identical issue.. however well chasing the high idle discovered faulter egr..bad diaphragm..replaced with new intake gaskets. Cleaned throttle.body. same results. Changed coolant temp. Same idle valve seemed loud in diagnostic mode. Changed. New one alot quietier.. set base idle..tps. Even checked base timing..all good. Idle good until shut off plug distributor back in.. restart at first good warms couple moments..idles down. Seems good did this once. Restart back to high idle..about same as u described. Replaced cap rotor plugs wires ignition module in distributor.. rechecked base timing and idle..with same results...fuel pressure also good. Idle or driving..no codes ..even after a week of driving with it like this..

 

ive done everything and cannot find the problem either man.. sorry 3 years dealing with it