89 camaro rs problems

help! i recently purchased an 89 camaro rs for my wife. 305 auto low miles
when we picked the car up it ran flawlessly.now in the last week or so this thing will not idle below 1500 rpm. i have checked for codes-none i have checked for external vacuum leaks-none checked wiring etc. it starts fine still runs fine other than the high idle.any ideas???

sounds like an IAC issue, but that should set a code. check and make sure nothing is holding the throttle blades open on the tbi

thanks for the reply. i will have the iac checked.did check for the throttle blade problem and found nothing holding it open.hpoefully its just the iac.
thank you once again.

IAC on a 3rd gen will rarely set a code. For the reving idle it is more likely the TPS (throttle position sensor) and it hardly ever sets a code either. If you got the TPS wet at all, throw it out and get another.

thanks for the reply.hopefully i can get this thing figured out and enjoy it