When the wheel and the tire rub together.
A defective vacuum line can cause a whistling sound when the vehicle is accelerating. A loose belt can also create a high pitched whistle sound.
Fuel is not good!
check your swaybar links and bushings
mine is a 2001 QX4 with the same problem. as far as i know, it could be a bearing problem.
bad wheel bearings
Most likely it's a CV joint.
if its a front wheel drive vehicle then it could be the axels
Low coolant causing air bubbles in the heater core.....
main shaft bearing
More than likely... the power steering belt.
you probly have a belt slipping, a can of belt dressing should stop the sound
If it sounds like its coming from inside the car its probably the fuel pump if not its kind of hard to say.