Hey guys, my 22RE runs great, except it makes a whistling noise every once in a while. I wish it was constant because then it would make it easier to diagnose. I luckily caught it on video when I was changing my oil the other day. What do you think is wrong?

[YOUTUBE]http://www.youtube.com/watch?v=plDj2mMMwLs[/YOUTUBE]

 

Do you have some sort of aftermarket air intake? Or something non-stock in the intake path?

 

Mine sounds like that at around 1K rpm and 2500+. I like it. Take a look inside the air filter housing on the bottom there should be a little tube that goes from the outside and directs air 90* from the inlet. Mine is gone and makes that noise. I bet yours is missing as well.
http://s286.photobucket.com/albums/l...4runner009.flv

ignore the second half of the video

 

A remote turbo? Haha. Yeah, sounds like something not factory is in your air intake.

 

Yes, the PO installed a K&N intake/air filter. I assume I should look/listen for leaks on the air intake, and if necessary take it apart?

I'll definitely check for that. And yeah, that low-pitched rumble at the end of the rev sounds the exact same as my rig.

Wish I had a turbo! But yes, it kind of does sound like a turbo whistle now that I think about it. Maybe I'll keep it...

Thanks for the responses!

 

any luck?

 

wow your truck sounds EXACTLY like mine, lol.
minus the whistle.

 

mine does the same. the following is only WHAT I HAVE ALWAYS FIGURED THE SOUND WAS, not the actual reason. thinking something to do with the air flow sensor/ filter. basically when you rev the throttle body opens. air flows. when you let off the throttle body closes though the motor still wants some air. so this sound is the re verb/echo of air being pulled past (and bouncing around) the throttle body and or air flow meter. when the butterfly (throttle body) is open the air flows and with the butterfly closed the air becomes turbulent and gets pulled through the butterfly at the same time.

The sound is very noticeable on a civic with a cold air intake/ cone filter with no other mods. you usually can't hear it in this application cause an exhaust or turbo or whatever is louder.

also looking back at other posts, the removal of that elbow inside the airbox (in my experience) will make this louder. or a cone filter.

 

Sounds like the cold air intake to me.

 

your engine sounds like mine

http://http://www.youtube.com/watch?...e=channel_page