Like a whistling type sucking sound at idle? I have a noise I cannot diagnose. I think it's a bad pulley. All of my belts are tight as hell and the noise persists. It is pretty embarassing.

 

at idle mine sounds like stock air intake. If I hi the gas at any pressure though you can hear it whistle, or however you want to describe that sound....

what is it idling at and how loud is it...if your sitting in your car?

 

at idle, there is no whistle.. a bit louder though.

 

Justy finished installing mine 1 hour ago. At idle sounds like stock, but at higher revs sounds mean. Good stuff

 

I just installed mine also, no whistle at idle, but when you step on the gas it definitely does. I dont know if this thing makes your car go any faster, but it sure sounds like it does!