ive changed out my ACT and my IAC reseted my EEC who knows how many times. but the car still idles high about 2000rmp then it goes back down, ill get a stumbling in in also ive been trying to find out for a long time whats causing this but no luck. i hear it in the exhaust the sputtering then it will clear up. i checked out my plugs and the car has been running lean, it has new O2 in it that replaced about a week ago. could the computer be doing this to the car or is it i have some kind of issues going on elsewhere or is just the computer going out. even while im driving around 65-70 and push on the gas i get valve knock, my timming is set at 12*.