merc 350 mag mpi, making sucking sound??

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 10-14-2013, 5:01 PM

Yesterday, it wouldn’t start. Checked dist cap, and it had moisture in it. Dryed it out and starts fine now, but now I’m heairng a loud air sucking sound coming from the throttle body. Does any one know why? shouldn’t that sound go away once you put the air filter on? its not as loud with the air filter on, but it never used to be this loud??? Is it bad to run this way?Did I lose a gasket or something?

(boardjnky4) · (boardjnky4) **Join Date: Dec 2011** 10-14-2013, 6:44 PM

IAC valve muffler is probably missing. Not a problem just annoying.

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 10-14-2013, 6:46 PM

is that in the throttle body? and leads to the IAC?

(boardjnky4) · (boardjnky4) **Join Date: Dec 2011** 10-14-2013, 7:22 PM

Yep, it's just a small little piece of fabric-like material that jams into the opening of the IAC (from the throttle body) that muffles the sound.

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 10-14-2013, 7:31 PM

Thanks! I’m picking one up tomorrow!

(malibu) · (malibu) **Join Date: Sep 2004** 10-14-2013, 7:35 PM

Tony Joe and I had an IAC muffler problem with our previous boat, an 05 Sanger - same engine as yours. The IAC muffler is a little foam square shaped device located in the throttle body. Ours was clogged up with black paint from the factory when the boat was new. Our Sanger wouldn't idle and the engine would die at important times like when you were coming into the trailer or a dock. It was a pain! We took it to several mechanics and no one could figure it out.When one finally did and he put a new IAC muffler on and it idled perfect.

(boardjnky4) · (boardjnky4) **Join Date: Dec 2011** 10-15-2013, 5:44 AM

Quote:

Originally Posted by malibu

Tony Joe and I had an IAC muffler problem with our previous boat, an 05 Sanger - same engine as yours. The IAC muffler is a little foam square shaped device located in the throttle body. Ours was clogged up with black paint from the factory when the boat was new. Our Sanger wouldn't idle and the engine would die at important times like when you were coming into the trailer or a dock. It was a pain! We took it to several mechanics and no one could figure it out.When one finally did and he put a new IAC muffler on and it idled perfect.

Had the same problem with mine. It took a lot of googling to figure that one out.

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 10-15-2013, 9:17 AM

I'm gonna be sooo happy if this fixes my idling prob! ( I had that too!) Where do you think the darn thing went? ( foam square) I had the spark arrester off, when I was tryin to start it Sun, and it kinda back fired thru the throttle body. Do you think it could have blown it out then? or sucked it in?

(boardjnky4) · (boardjnky4) **Join Date: Dec 2011** 10-15-2013, 3:25 PM

It shouldn't idle badly if it's simply missing. If one exists and is clogged, that will cause rough idle.

(tonyv420) · (tonyv420) **Join Date: Jul 2007** 10-16-2013, 10:09 AM

Back up and running! Seems to idle a lot better. Going out tomorrow for a test! Still sunny up here in the PNW this week, and the temp is perfect at 65 degrees!