I have an auto XA with AEM cold air intake with 9k miles on it. I've noticed a "whirring/whistling" noise happening intermitently when I accelerate from a dead stop. This only happens when I have the AC on, and when it is hot outside. It doesn't make the noise after I have driven the car for about 10 minutes or so. It' a really noticeable sound though.

. It kinda sounds like a loose belt, but I was wondering if anyone else has had this happen to their car. Is it a tranny issue? Intake issue? etc. Should I be overly worried.

I just know when I take it to the dealer, it's not gonna make the noise cause problems never perform on cue. The car will be warmed up by the time I drive there, and the technician is gonna look at me like I know dick about cars.

Our engines, 1NZFE, have timing chains:
http://www.scionlife.com/forums/viewtopic.php?t=6659&highlight=chain

That could be it. Does it whistle, whir when let go of the gas? If so that could be it too. Not a problem but chains are better than belts, IMO. But maybe it's an AC. We have small engines with a small radiator. I think I hear that too. Especially stopped at a light with AC on, then the AC or engine starts kicking in. Dont have a CAI though.

Well cold air intakes do make a whining sound during acceleration.

My CAI doesnt make much of a whirring noise when aceleration, at least not that I can hear. Of course now that I've installed my CAI my engine makes a much more throaty growl. I kinda Like it.