This worked with my wife's '86 Legend that had a weird idle issue:

Pull the Alt-Sense fuse for about a minute then replace it. I dont know if there is something labelled Alt-Sense on your car, but I think it would be in the fuse panel thats under the hood. Its probably a large relay, larger than the others.

Previous to doing that, I tried resetting the ECU by pulling battery power and the ECU fuse, but that didnt help. Pulling the alt-sense fuse did it.

-Chris