2006 320 Sundancer High Idle

[Drew Schmidt]

I recently replaced the IAC and oil pressure sensor (a week prior) on my port engine. After replacing the IAC, the engine idle was 200 RPM higher than the starboard. 800 port engine vs. 600 starboard engine. I ran the boat for 30 minutes and when reducing the throttle all the way down but keeping it in gear the port engine was at 1000 RPM and the starboard was 700. When shifting to neutral the port engine would jump to 1250. I was not happy to have to shift it into gear. I am trying to research this issue and not having luck. Has anyone else run into this?

 

[Todd320]

Did you use Mercruiser IACs? If not, try those. Maybe first, try swapping the IACs, and see if the high idle follows. Of course, could be an unrelated issue, maybe the throttle cable is not going all the way back to idle?

 

[Drew Schmidt]

I did not use the Mercruiser IAC's - they were hard to get. I researched and found that the 2002 Ford Windstar 3.8l V6 uses the same IAC. Went to my local auto parts store and found a good brand and used it. Actually used it on the starboard engine first 3 weeks prior and got the same one for the Port (problem) engine. I have also not swapped the IAC's yet but is on the to do list. I did not think to check the throttle cable, is that an easy find? Thanks for the feedback.

 

[firecadet613]

Easiest fix - take it back and swap it out. You may have gotten a bad one.

That's my first thought, especially given the starboard engine has no issues with the same brand / model IAC.