When I accelerate onto the highway there is a noise that gets increasingly louder. It sounds like a high pitch whining, almost like a soundthat would be coming out of a synthesizer. I would appreciate any feedback on this. Thanks for your time.

Brett

 

had a F150 did this once the previous owner had put that fuel thing in his airbox, sounds like a turbo whine on a car, if you had it since new, check your airbox for cracks, or holes.

 

Another possibility is the serpentine belt idler pulley.

 

wouldnt an idler pully more be a squeal?? I think like turbo whine when you say symthizer

 

it is definately more like a turbo whine than a squeal. I can't find any modifications / holes / cracks in the airbox either.