I have a 1999 prerunner, 2WD, 4cyl, 55,000 miles on it.
Ever since I have owned it (only about 2 months) I have noticed that while driving and pressing the gas pedal, I hear nothing unusual, but if I want to slow down, and take my foot completely off of the gas pedal, a very hard-to-notice, high pitched 'whistle' begins. I can not pin point where it is coming from, and it is so subtle, the driver would probably be the only person to hear it.
Anyway, as soon as I give it the slightest amount of gas, the whistle stops.
I am not touching the brake pedal at all when this happens, and it is not coming from the radio speakers.
thanks in advance! Jazz Mann