i took this quote from thefultonhow in one of your older threads that asks basically the same thing...maybe the engine is going in limp mode BECAUSE of said idle control sensor? its a start...One of your sensors (possibly the MAF, possibly the O2, possibly the knock sensor, conceivably something else) is outputting bad data, which causes the ECU to cut power and prevent you from revving above a certain RPM (I believe it is 2500 rpm).