I'm slowly remedying the crappy idle produced by my '87 non-turbo 744. I've just installed a new AMM which helped the most. The IAC is also new and the oxygen sensor is less than a year old. The car runs pretty good most of the time. However, I still intermittantly experience an almost cyclical engine speed fluctuation which is most noticeable at idle or low throttle, and especially when coasting to stops. The engine speed cycles up and down, I'm guessing 100-200 rpm, about every couple of seconds. It seems to get worse with higher engine temps and I also think it gets worse when I'm doing a lot of short, frequent trips where I'm starting and stopping the motor a lot. It may go away on its own but usually continues until I switch off the ignition. The throttle body is immaculate and I can't find any vacuum leaks. Plugs, wires, cap, and rotor are newish. I hope somebody recognizes something simple that I'm overlooking here! Season's greetings...