For every cold start on the ES, the car's idle is OK. But when I rev it (with pedal to the metal), it seems as if the engine "sputters"? The description is like someone repeatedly stepping on and off the gas pedal really fast. Example, I start the car, rev, and tach goes up 2000rpm, less than a split second, drops 200rpm, and less than a split second goes up 600rpm, down 200, up, down, up... yea. So this was geting annoying. Could it be possible that it's an air induction related problem?