My 1994 tempo makes a whining noise when I turn it off. It might be doing it when it is running but I cannot hear it. I suspect some kind of vacuum leak or perhaps some carbon build up. It has 155,000 miles but runs fine. Air filter is fine also. Sounds like it is coming from the throttle area, but not sure. Any ideas?

 

Sounds like a vacuum leak that winds down after you shut it off. Or could be radiator/engine overheat (fan not turning on and sensor not reading it or fluctuating disguise -(car cools and reads normal when in motion (air pushing in radiator cools it) but heats up if idling and not moving for 5 minutes to a half hour). The whining can be normal antifreeze blow-off from the pressure cap (only holds certain lbs. of pressure) too (if you fill the radiator over full repeatedly).