stalling at idle

[jptige22]

OK, 2001 22ir with merc 350 mag mpi(50hrs on motor), first time out this summer. Water leak. Alarm beeps twice. Won't idle. Turned on bilge pump, put it on the trailer. No more water. Fixed the leak, changed tranny fluid, changed fuel filter. Out for a test on the water. Still beeps twice and stalls at idle. Pulled a wakeboarder,got hot. Put it back on trailer. Changed water pump impeller(shredded). Changed spark plugs, looked for other problems. Nothing found. Back out on water. Beeps twice and stalls at idle. Beeps twice at high speed. Question. What is proper idle rpm? Any other suggestions? Maybe IAC?

[huntingwiley]

Mine was doing the same thing. It was the IAC. I tried cleaning mine with no luck...Talked to a couple Merc mechanics and they said the IAC going bad on these morotr is pretty common and cleaning them almost never works. I changed mine out and all was fixed. Motor runs like new and warning alarm stopped.

[jake's02-22i]

sorry might be dumb but what is the IAC?

[huntingwiley]

IAC-Idle air control valve

part # 862998

http://www.mercruiserparts.com/Show_...=THROTTLE+BODY

[R&T Babich]

... Beeps twice and stalls at idle. Beeps twice at high speed. Question. What is proper idle rpm? Any other suggestions? Maybe IAC?

The beeping at idle is probably the low oil pressure warning.
Our oil pressure at idle is 18 lbs.
The beeping at high speed might be low fuel pressure.
A clogged anti-siphon could cause fuel supply fluctuations.
The anti-siphon valve is in the fitting in the fuel tank the fuel hose is connected to.
The check ball inside could be corroded and stick blocking fuel flow.
A fuel pressure tester or a small gauge screwed into a port on the fuel rails would allowing monitoring the pressure.
Ours is around 25 psi when the ignition is turned to ON.

[jptige22]

Awesome, replaced the IAC valve, 5 minutes, boat in the water, runs like new. Thanks for the tip.

[XXticy]

I keep getting a low oil pressure alarm after I have ran the boat across the lake and everything has 'warmed' up... The oil pressure usually hovers around 40-45 when riding across the lake and after 10-15min i get to the cove and pull it to idle and the pressure drops to 20 (right at the top of the red) and I get the alarm... Boat runs fine but the alarm is annoying and not sure why it's going off... Any suggestions?