I have a 83 t-bird with a 5.0. In cold weather it idles at a high speed around 40 mph in drive. I changed the throtle position sensor TPS, but it still idles to high. If any one has any ideas I would appreciate it.

Thank you..

 

clean or just replace IAC motor and clean you throttle body with some carb cleaner take the air intake hose off spray into the throttle body and open the flap spray around it wipe out if needed with rag

 

In addition to labc's suggestion some of the other possibilities for a constant high idle might be , possible charging system problem, coolant temp sensor, vacuum leak.
You didn't say whether the check engine light came on , did it?

 

No the check engine light has never came on. I forgot to say it was fuel injected as well.

 

yea hanky i forgot about the vac leak around the upper intake take some carb cleaner and spray all the vac lines if rpms race up higher thats the right line and spray around the base of the upper intake as well

 

I have had occasions where the linkage had become gummed up and all it required was to make sure the linkage was able to return to the low idle position.