Hey guys. Got a 2003 fountain 27 fever 496ho. Can't seem to get boat past 4600rpms. Runs great below that. There is 2 red lights on dash that come on at those rpms. I scanned it and found a iac code. I have a new iac valve that is going in today. From what I have read the iac really only controls idle. It is idles perfect. Is it possible that code will limit engine rpms?. Is there something else I'm missing. Boat was just purchased and don't know any history

496 HO 152 IAC Output Code

My IAC experience.

Yes IAC can put engine in guardian mode and limit rpm.

Shouldn't that show up in scan history?

Yes. You will see a Guardian and overspeed fault. Scanning thru freeze frame data you can see engine data when these faults occured.