i have a problem...i got my drive belt replaced and a sensor in my tranmission replaced as well...well ever since i got it back it has been idling really rough sometimes to the point to where its about to stall out and sometimes it backfires...and it gets worse when the air is on..now could this be a problem with the belt and how they put it on or what...i mean i am taking it back asap but i would like to know..thanks..