[CaseyVR6]

Throttle body almost for sure, it at least needs to be cleaned and then re-adjusted. Also sounds like a bad cat. Sorry dude... new cat will run $1200 at the dealer ($500 if you get a recertified) and a throttle body I've never found for less than $700. One of the pro's should give you the advice any minute that either calls me a fool (it happens) or they'll say "yup, sorry" (or something like it)