97 GT. Cannot shake this "High Idle" P0507 DTC. I replaced the IAC & MAF sensors. I also swapped the TPS with my sons Monte Carlo with a 3.8L engine that is not getting any codes. I do notice when cold sometimes it can Idle pretty high but then it seems to idle down to normal when warm. I have no idea what to check/ change next to keep the SES light off? It is always just 1 P0507 code.