My roomate had a 86 740 turbo he got so fed up with i talked him into taking my crx for a it in a trade :> however im still left with this problem. the car starts up fine and idles, once it warms up a little it starts to idle a little rough if i put it in drive hold the brake and give it gas the rpms climb then fall back but the tach does not fall to 0 tho, then it picks up and drops picks up and drops the problem has goten worse and worse over time and now the car is not diveable other then idling it around the yard he has replaced the following: maf, wires cap & rotor, wiring harness (it was frightning)the ignition controll module and the fuel controll module both fuel pumps and the fuel pump relay, fpr, and the entire intake manifold incl tps fuel injectors and throttle body (he worked at a volvo repair place so it wont a big deal gettin the parts) all of the turbo and vacume hoses have been checked and replaced as needed the engine and turbo have under 100K on them and are in great shape so any suggestions folks ? Thanks !