I've got a '97 318is, manual transmission, w/ about 125k miles. After getting new tires installed last month, the car would act like the cruise control would suddenly be activated, and the engine would rev to 4-5k when I pushed the clutch in. This happens in any gear, any speed. It goes away completely when the ASC is de-activated. However, the ASC diagnostic scan showed no faults, as did all other scans. Presumably the wheel sensors showed no faults. One mechanic changed out the idle control valve, replaced a worn cruise control cable, cleaned the throttle body/air intake, all with no change. Last week, I changed the plugs/wires and also the forward O2 sensor as part of regular maintenance, and the problem pretty much disappeared. The ASC light starts to flash when accelerating hard (no, not spinning the rear wheels--this is a 318), and the car tends to surge a bit on steady cruising. I've had two very experienced (independent) BMW techs look at it, do diagnostic scans, and consult with dealer techs, and they don't have an answer. A new ACS unit is $1,000++, and I don't think that's the problem. Any ideas??
