Humming noise from front left Options

[boomer3]

Hey guys, just picked up a 94 gt4, i'm loving it! I've noticed a bit of a humming noise from the left front end of the car. The noise is not related to rpms, or whether the car is moving or not. I can hear it while i'm driving, but it comes on and off periodically if i'm idling. Also, when idling if I open up the hood it appears to be coming from somewhere near the airbox, and sounds as if its some type of auxiliary pump or something. When it goes off, I can rev it up a little, and it usually comes back on. Let me know if this is making any sense at all. Thanks for the input!

[Culpable04]

unless you have an aftermarket pump, you shouldn't be able to hear it inside the car at all, maybe your pump is on its way out, thus making that noise, the pump is right under the battery, you can access it by taking the wheel off on the pass side of your GT4 ( driver side for us.

Jack the car and take the wheel off, with the car in NEUTRAL and the EBRAKE on, let it idle until the pump comes on, if it's the pump you'll know right away.