David... that's EXACTLY what I'm saying... that's why it's weird. The car doesnt shake when the AC is on but when off, the car shakes and has a teeny sputter like as if there was a misfire... the engine has that prr prr prr prr prr prr prr noise.. but when the AC is on, it is less shaky. I dont even know if the car has an idle control valve/relay... I think it IS computer controlled... I dont know what to do... I'll check if the car is running lean or whatever...
'94 MB C280 Lorinser Sport Suspension