2003 Jetta, 2.0 engine, no turbo
The serpentine belt is whistling at high RPM’s when I press on the pedal, and it stops immediately when I let off the gas pedal. It’s coming from the serpentine belt, but the belt itself looks ok. I’m thinking it’s the tensioner or the pulley, but googling hasn’t been very helpful. There is no check engine light or any other light on.
What do you think?
Edit: I should have mentioned this as it is relevant, but the AC on the car has not blown cold in over a year. While driving the car, I put 2 and 2 together and remembered that the serpentine belt powers the AC compressor. Interestingly, if I turn on the AC the noise completely stops. For now I am just going to drive with the AC turned on, but I’m not sure why turning it on fixes the problem.