I put several thousand miles on my DeLorean before I realized that someone had backed out two of the idle adjustment screws pretty far. I just lightly re-seated them using my fingers. It changed nothing. My car idles at 950 RPM which is on the high end of the allowable range, but runs great. While you are looking around in there getting familiar with the engine, check to see that all of your spark plug boots are seated properly. Two on my car were loose, but it didn't seem to make a big difference. I keep finding little weird things that a previous owner was responsible for. For example, I had a CD jewel case wedged between the windshield drain and the fuel pump cover to keep water out of the tank. I eventually got a new fuel tank boot cover for it. Supposedly years ago the supply ran out and people had to improvise. Walt Tampa, FL