Have 84 with 2.8. Most of the time it idlels at 1000 rpm or more regardless of if its just been started from cold or if you've been driving it all day, summer or winter it doesn't matter, most days. Then the next day it may idle fast when you've been driving it and you stop somewhere for 10 minutes get back in it crank it up and it won't idle fast enough to keep running and you have to keep your foot on the gas to keep it running when you come to a stop. Even in any of these conditions the car runs great, no rough idle, no smoking, no bad effects at all. What gives?