i realize its normal when you down shift too far and your engine overrevs...leaving it after it winds back down to idle it gives off the sputtering missing sound....the thing i hear strange is you hit the I key...shutting off the motor...and it winds down...but still giving off a sputtering and missing sound....a real life engine doesnt shut off with sputtering and misfiring when you turn it off does it??...i think its something missed in the realism of engine damage...