It seemed to happen when I got the sound system put in, but that doesn't make any sense. It happens in gears 1-3, but only when accelerate quickly. It sounds like a whistle getting louder as the car gets faster. Any experience? Thanx.

 

Could it be ground noise coming from your speakers? That is very common. Check your grounds on your amp/deck.

 

Sorry, but I forgot to add the fact that it only seems to happen when the A/C is on. I will give your suggestion a look at though. Thanx.

 

Even more likely to be the ground. This tends to happen mostly when accessories are running. Make sure your ground cable is the same size as if not bigger than your power cable, and make sure it's grounded to bare metal.