HelloMoto

Alright, problem is still happening.

One thing I forgot to mention was if I rev it while in park, the sound does not occur. I would assume the air intake would still be sucking in air while I rev the engine in park, right?

If so, that rules out the air intake. We went through a bad snow storm last year here and I've been having some problems ever since. I also think there might be an issue with my rear differential as when I turn at low speeds, my truck vibrates.

With testing in park like I have and revving the engine, does that rule out it being an air intake issue?

schissler

thats just what a cold air intake does.

my honda makes a whistle while using light throttle at slower speeds. everyone i know that has an intake does this.

schissler

there is no load on your engine while parked. it does not suck the same mass of air.

your rear end vibrates when you turn because you probably have a limited slip differential.

edit: its nothing to worry about and if you want to test, put your stock intake back on and see if its gone.

HelloMoto

I have a buddy who has the same model K&N air intake on his Dodge Ram and it does NOT make this sound, so that cannot be the problem.

07harleyD

Im had a whistle in mine when I hit the gas and it turned out to be my passenger side manifold, it blew a part of the gasket out.

schissler

Posts from other forums confirmed what I've stated above.

http://www.allfordmustangs.com/forum...m-whistle.html

http://www.toyota-4runner.org/5th-ge...e-whistle.html

HelloMoto

I guess my point is even if it is the intake, that is not how the intake SHOULD sound. I've looked up numerous videos on youtube to try to compare with the sound I am hearing, and can hear the whistle you are referring to, but this sound is different.

I've also tuned my truck with a Diablo brand tuner, so the gear ratio is different(better gas mileage/horsepower).

It sounds like the sound brakes make that have started to wear down, but not a full blown grinding noise.

I also tried recording the sound of it, but I don't have the proper sound equipment to cancel outside noise. I'm about to just take my cell phone and tape it to the inside of my truck and see if I can get a good sound recording of the problem.

Edit: Here's another forum post about a similar problem:
http://www.scionlife.com/forums/showthread.php?t=185124
Yes, it's a scion, and mine is a Ford, but it's pretty much describing the same problem I am having, and it looks like it had something to do with the Throttle Body. So this makes me lean more towards that being the issue.

BISCUT

I have the K&N system as well and thought I had a bearing out fromt hat same metallic sound. Bothers me 2. But I look for a while and spoke to K&N and it does seem to be par for the course.

I've had a bad bearing on an alternator (different truck) and the noise is different. This noise sounds like its from your fornt end and isnt there when you stomp on it. I think were are talking th same noise. Just let it go! The benefits from the K&N outweight the noise and it DOES sound differnet on the street than what you get in the cabin.

But I get ya, it does make you think WTF is wrong?

HelloMoto

Definitely don't want to just 'let it go'... I want to FIX it so the noise no longer exists. It does not sound like a turbo charger, it's a metallic hissing noise.

Taken from another forum,

"Update on the hissing sound. When I installed my Fastman Throttle Body today, it eliminated the hissing sound coming through the intake.

Conclusion: The hissing was either being caused by one of the following or a combination thereof: positioning of the tubing, angle of install on the throttle body, bad install, or (most likely) the lip of the throttle body that the air has to pass by is much slimmer now and more aerodynamic."

So I doubt it's a NORMAL sound.

mr7confused

Any update? I have this sound, bad. I want to blame it on an exhaust leak between the manifold and the y-pipe..