so i got my K&N CAI last week and i started hearing this whistling. well im like wtf mate what could that be so i pop the hood and have my friend slowly drive up the driveway.

well it seemed to be coming from the filter, so i was like now i have to buy a new filter.

so i got the new filter today and it does the same damn thing


so does anybody else's whistle? its only at lower speeds usually in between 1-2000RPM and when i press on the gas


if no one else's does this then im about to scrap the k&n for an AF1 or something

 

With just about every intake you are going to hear a lot more air being sucked in. I have a K & N and I guess you could say it whistles. It it normal and there isn't anything wrong with that if that is what you mean?

 

theres nothing wrong with it and i expect to make more noise but i dont see how its whistling

 

i got an older truck (98) and at low rpm you could say it whistles or whisps...but when you get to the 2500-3 grand range does it growl??? thats how mine works

 

mine makes a loud sucking sound i have a 12" k & n filter on an 8inch long piece of pipe attached to my turbocharger.

i wouldnt scrap the K&N just because of the whistle, my friend had a mac cai on his truck and it did the same whistle thing your talking about.

 

For me (and AFE) it kinnda whistles, but it's more a noise of it sucking in air. It only does it when I push on the throttle in the low RPM's, and only for a little bit. If I really look for it, I can make it slightly whistle constantly, but it's only at a very small RPM range.

Really, you get used to it, and I personally like it, especially the growling part.

 

im about to buy an AF1 just because i like the sound of the whistle.. it almost sounds like a diesels turbo.. i like it a lot... almost all CAI will whistle.. your hearing the CAI do its job, suck in more air!!

 

If you have a whistle from your K & N I would bet you removed the small black plastic muffler that was installed by Ford. I don't have a picture but it is about 2 by 4 inches, black plastic with a hose at each end.
Mine did the whistle and to get rid of it I bought a small piece of hose with a 90 degree bend in it and put the muffler device back in line.

 

could you get a pic of that idk what your talking about

 

just like everyone else says, its normal. mine whistles really loud when i jump on it at about 3k rpm. no need for a new filter.

 

My K&N just roars.

Put an exhaust on for more sound.

 

My 3" AF1 never whistled, but there was a distinct "whoosh" sound when steppin' on it from low revs.

For some reason that sound has all but disappeared since I started running the tunes from Troyer.

I think the induction sounds are normal with any "cai", but there shouldn't be anything high-pitched. Like a whistle noise.

 

see thats what im thinking, mine does roar when i step on it and i know they are louder but i wouldnt think anything would be making a whistling noise.


it sound just make a whoosh sound from sucking air in.

this is a loud pitched whistle too, i can hear it inside the truck when i dont have any music playing and the windows up.

 

Yeah, there has to be a leak or loose connection there somewhere. K&N is a high quality intake... you shouldn't be getting a whistle.

I'd double check everything (sounds like you have already though), and if you don't find the problem try contacting K&N. It sure doesn't sound normal.

 

It's normal. If you have a throttle body spacer then it will make the noise louder. Like Msall said, changing out the exhaust will produce more of a roar.