When my engine is cold it immediatly revs to approx 2000rpms on startup it then gradualy reduces to approx 1000 when hot. I'm pretty sure it didn't do this before I replaced the iac. The new iac acts completely normal and lowers the rpm in steps but doesnt't bring it completely down. I have been getting a code for bad intake air temp but it tests ok. Any thoughts???
Thanks and Merry Christmas
Gordon