2007 252 Alarm - 2 beeps

[SamIAm]

2007 252 with Merc 496

Hi all,
We have been using our boat a lot this week (family in town). Yesterday the alarm under the helm started to beep twice every minute or so. Also noticed the motor is running rough and sometimes dies when at idle (all new symptoms).

I took her back to the marina right away and did some research on-line. I think it could be the IAC valve (motor).

Does anyone have experience with a 2 beep alarm and/or faulty IAC valve? Just want to ensure I'm on the right track. Meanwhile, I'm looking for a IAC replacement valve at local auto parts stores etc..

[Big Block Power]

Yep that's what it is. It's a ac Delco part from a chevy truck. Mine had a number on it ac147. But which style do you have. Did you remove it yet. There are 2 styles. 1 GM 1 Ford.

[SamIAm]

Thanks BBP,
I plan to remove it and take it with me to the auto parts store(s) later today. Thanks for the PN info above...that helps!

[Big Block Power]

Thanks BBP,
I plan to remove it and take it with me to the auto parts store(s) later today. Thanks for the PN info above...that helps!

I always have a spare on my boat. Don't go off those part numbers. They were just examples.

[SamIAm]

Idle Air Control (IAC) on a 2007 252 with Mercruiser 496 (8.1 ltr).

Symptoms (in my case) - 2 beep alarm (every 60 sec or so), rough idle, motor shut down when going from cruise speed to neutral (idle).

I'll start by saying I'm not a certified mechanic, so below is for reference only.

The IAC on my boat was painted black and a little hard to find without knowing where to look. It was located towards the back of the motor near the stern. I removed the IAC (2 bolts and electrical connector). Mine had 862998 (part number) stamped in the casting. After installing the new IAC, the alarm went away and the boat ran great. The only difference is that there is a slight 'speed' pulsation while in idle (maybe a 100 RPM pulsation). It goes away when I apply throttle (only occurs when in neutral and in idle). It does not seem to affect anything else, it's just different than before. Is this slight pulsation normal? If not, is there something I need to adjust?

[akorcovelos]

Check the yellow fuel vapor lines for clogging, as well as the tube the IAC slides into.

[Cobalt272!]

Anyone know if it's common to have an issue with IAC valve and NOT get have the beeps activate?

[akorcovelos]

Anyone know if it's common to have an issue with IAC valve and NOT get have the beeps activate?

My ‘96 had a bad IAC and I had no beeps at all.