Noise like tuba horn from intake at power off

bsamole

Registered User
I have no clue what is making this noise. It sounds just like someone blowing into a tuba horn for about 1/2 second. I removed the air filter and the noise is coming out of the tube leading to the air filter. The noise only happens about 2 seconds after the engine is turned off and only lasts for about 1/2 second. I can start the car and turn it off in 5 seconds and the noise happens. I drive for an hour and thrn it off and the noise happens. The car has 213,000 miles and still runs strong. The noise started about 3 weeks ago. Happens every time the car is turned off. No modification or maintenance has been made in the past 2 months. Any thoughts would be appreicated. Thanks
 
I've heard of this before.

Look to see if your noise coincides with the boost guage zeroing out after you cut the ignition. I'm pretty sure the noise resides with your boost bypass valve. Try spraying it with WD-40 and wiggling it back and forth with the engine off.

It could also be a hole in the bellows of your IAC. That could be making the noise as the IAC returns to neutral.
 
I thinks its your IAC also. Does you car idle high? If it starts idling high in the future its most likely your IAC.
 
re-moan

Mine started doing that and then the idle started creeping higher and higher after a month! Changed out my IAC I bought from ford for $106 car runs Great now. I have a 165,000 on mine. They sell them at other places but from the search here everybody says to use the factory one! Good Luck!!!!
 
Ahhhhh...The famous Ford "Moose Call"...LOL!!!!!!!! :D :p
Yeah thats the IAC so get a new one. I wonder if they built it that way so it would be very obvious to the mechanic,tech or whatever they call them nowadays. LOL!!!!!! :D :)
 
You guys are the best. Post a question and wam bam 4 responses. Thanks! I've never heard of an IAC but I'll ask Ford for one tomorrow, bet they know what it is. Then when I have one in my hand I'll look for the same item on my SC and replace it.
Thanks!
 
bsamole said:
I have no clue what is making this noise. It sounds just like someone blowing into a tuba horn for about 1/2 second. I removed the air filter and the noise is coming out of the tube leading to the air filter. The noise only happens about 2 seconds after the engine is turned off and only lasts for about 1/2 second. I can start the car and turn it off in 5 seconds and the noise happens. I drive for an hour and thrn it off and the noise happens. The car has 213,000 miles and still runs strong. The noise started about 3 weeks ago. Happens every time the car is turned off. No modification or maintenance has been made in the past 2 months. Any thoughts would be appreicated. Thanks

Your idle air control (IAC) is bad. When you shut the engine off outside air is supposed to refill the IC tubes and that normally comes through the PCV. When the idle air control get's a crack in the bellows air goes through there instead. Make sure you buy a Motorcraft unit as others don't work correctly.

Jerry
 
Its the larger sensor on the throttle body, the other smaller rounded one is the throttle position sensor (TPS). Just in case you were wondering. :)
 
This is my pitiful attempt at photoshop but you should understand it.
The black thing with a grey wire plugged into it and encircled with my beautifull red art work is your IAC. (Idle Air Control) :D
Hope this helps you. :)
 

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More than likely it would'nt cause a cold start problem because at cold start the idle is raised by the computer anyway. A ruptured IAC just acts like the valve is open farther than usual so the engine idle goes up. The leak in the diaphram leaks more air into the engine and that rupture makes that moosing or honking goose sound. The sound is a dead giveaway to a bad IAC. :)
 
Thanks for all your responses. Mike your photo was great, wish I had that great looking engine. I'm convinced from all of your responses and a search (now I know to search for IAC) that the IAC is 99.8% the cause.
 
i got a spare good working IAC sitting around from my 91..

ill ship it to anyone who wants it for 100$ CANADIAN(80$ american)
 
The last IAC I bought new from Ford cost me a wopping $76 brand new, However my buddy Dan Newman no longer works at the dealership so..........
 
MIKE 38sc said:
The last IAC I bought new from Ford cost me a wopping $76 brand new, However my buddy Dan Newman no longer works at the dealership so..........


Dan Newman can be reached in Charlotte at 704 532-3284 (direct number to his office) or 800 847-2047 (ask to be transferred to Dan) or on his cell 704 307-9933.

Eddie
'90 5-speed SC
'97 4.6 LX sport
 
Yesterday I ordered the IAC from the local Ford dealer part number E9SZ-9F715-EA for $95.70 plus tax. I have no connections. Installed the part today and ya'll were right on, no more tuba. The diaphram on the old IAC was split at one of the joints.

Thanks to all, expecially Mike for the photo and circling the part.
 
I replaced my IAC a month ago. I didn't see any damage, but it was covered in oily sludge stuff. How the hell does that get there???
 
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