saveme20

i have a 2001 IAC that lately has gotten really loud like i hear it pulling air really hard but no change in performance that i have seen or idle anyone have any idea whats going on?

Sxynerd

Your IAC isn't getting loud. Do you know what an IAC is and how it works?

saveme20

yes i know what it is

Z28KLR

I'm no ASE certified technician, but I would think that if there's any negative issue at all with your IAC that idle quality would suffer (hence the term, Idle Air Control), and the engine would be on the verge of stalling. Those things are fairly sensitive, if there somehow were to be a restriction in the line or if it became unhooked or had a leak anywhere between the plenum and intake tract you would have dramatic decrease in idle quality. What makes you sure it's your IAC? If your idle is smooth, I'd look elsewhere. But if you're convinced it's your IAC, pull it off and inspect the tubing and that little black box for leaks or restrictions, maybe even pull the plenum off and spray it out with some carb cleaner if it needs it (that last one's kinda farfetched, but worth a try I suppose).

Z28KLR

@ sxynerd-

I understand the basic concept of IAC, but I'm always down with being enlightened if you feel like sharing some stuff the rest of the class might not know.....

WannaBeGearHead

Fixed ^^^

saveme20

beacuse it goes in and out whenever it kicks in like when you have the heat on or anything like that that takes power and thats where the noise is coming from and i checked the black box too no leaks should i replace it cause iv never heard one that loud its wierd

WannaBeGearHead

Could be your alternator going bad.

Sxynerd

In all my years i've never seen a loud iac. i highly doubt that it's bad enough for you to "think" you hear it but not bad enough for it to screw with your idle & decay. Hows are your a/c clutch bushing, are all three still there?

The block box is a Helmholtz resonator and does nothing more than give the air flow a chamber and the sound associated with it a place to expand into and create less airflow noise. They say it also helps even the pulse flow waves going into the iac but i diagree. I dont even have one.

02BLK GT

Try checking if its something else I also hear a sound like that on my stang, I got under my car and the noise was louder, I think its an exhaust leak since my car is lowered and where I live theres a few of speedbumps.