hello, a month ago, i tried to start my car but didn't keep my hand on the key long enough to crank but it fired once and backfired in the intake. i cranked it after that and it revved up to 3000 rpms and wouldn't go down( the throttle was closed). i had a known working spare tps sensor so i put it on and yesterday it still does it. would it be possible that the IAC is sticking fully open letting air bypass the butterfly flap and making my car rev like this. anybody else know any suggestions. thanks, i searched