Yes, and when they go completely bad, the alarm will beep every minute or so.

You can check it before changing it by disconnecting and then starting, your idle speed should rise as normal, reconnect and start again, if your idle speed is normal it's probably not the IAC.

Rick

I'll have them check it today, from everything I've read, the IAC sounds like the culprit.

Hate the coincidence of having just gassed up and have the alarm go off inside of 2 miles. But no ethanol through this engine yet, and I don't think any alarm will go off for water or bad gas.

I'd rather it be a bad IAC than the gas

Hope that's all is!

It was the IAC. Runs like a charm now.

Thanks to all.

My cousin had two different boats with Merc's 6.1 (377) with an IAC going bad. Something wrongs when a control module without any moving parts goes bad.