When I'm driving along (any speed up to about 40 mph), every time I ease off on the accelerator I can hear a quiet sort of high-pitched squeaky 'whistling' noise for a second or two, which seems to be coming from either the back of the dash somewhere, or somewhere further forward. I also hear it when going over bumps in the road, possibly coming from the drivers side but difficult to tell really. I only get it when I moving, so not if I rev it and ease off when stationary.
Any thoughts what could be causing it?
I get a similar sounding noise sometimes when I put the a/c on from cold and turn the fans on quite high.
If anyone knows how to get rid of the noise - apart from turning the radio up!
Thanks in advance.