Whistling noise with low acceleration K&N Intake
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From: Burleson/Athens/Brownsboro, TX
It's probably the throttle body only being opened slightly and I think that's what causes the noise. I eventually plan on getting a new exhaust system as well, so I might eventually not need it as the exhaust makes a good noise at any speed and might dampen the sound coming from the intake.
Would it be possible to change the Throttle Body to get rid of the sound?
Would it be possible to change the Throttle Body to get rid of the sound?
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Jim
Jim
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From: In the fast lane from LA to Tokyo...
It's probably the throttle body only being opened slightly and I think that's what causes the noise. I eventually plan on getting a new exhaust system as well, so I might eventually not need it as the exhaust makes a good noise at any speed and might dampen the sound coming from the intake.
Would it be possible to change the Throttle Body to get rid of the sound?
Would it be possible to change the Throttle Body to get rid of the sound?
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Joined: Dec 2012
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i just purchased an k&n for my 2008 and I got the same whistling noise under acceleration. I think I have narrowed it down to where the 90 degree pvc adaptor meets the throttle body, the gasket they provided didn't seem to do a good job sealing. I picked up some of that "make-a gasket' goop and sealed all around my throttlebody to the adaptor. going to let it dry up and seal good and do one more coat just to be safe, hopefully this does the trick! I basically sat in my engine bay with the engine running.. and made damn sure to stay away from moving parts lol. and ran my hand around the throttle body, I found the leak there. hope this is it!!
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From: Tenneessee
^This. I have a new 2012 5.0 with the K&N CAI. I think it is because there are no silencers (little side tubes) to help disrupt the Air as it enters the throttle body. Mine makes a fluttering, hammering sound just as you barely touch the throttle. I did take off the large K&N filter and bought a Airaid dry synthamax filter that was slightly smaller. It helped with some vibration I was getting from it. As long as you have a free flowing tube you will not get rid of the sound 100%.
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Joined: Jan 2004
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From: Tx.
I had a 2000 F150 with the 4.6 and the K&N intake and had the same whistle. After a couple years living with it, I modified the intake. I used the tube from the throttle body and adapted it down to the original airbox. I added the K&N flat filter to the stock box then built a new input tube to eliminate the restriction in it. With it now pulling air from the fender in the stock location, the sound was gone.
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From: MI
I had a 2000 F150 with the 4.6 and the K&N intake and had the same whistle. After a couple years living with it, I modified the intake. I used the tube from the throttle body and adapted it down to the original airbox. I added the K&N flat filter to the stock box then built a new input tube to eliminate the restriction in it. With it now pulling air from the fender in the stock location, the sound was gone.
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Joined: Jan 2004
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From: Tx.
I ran it with the K & N flat filter for 7 years before trading the truck in. At that time it had 150K miles and never any trouble with the maf. Just dont over oil the filter after cleaning.
