Even though your radio is off, the high-pitched sound is caused by the
stereo or the speakers or something. My brothers '88 90Q and '90
90Qcoupe both had that irritating whine, until he had a new CD player
installed. The guy who put it in said that somthing was wired wrong or
weird or something, I can't remember but he fixed it. Electrical is not
my area. I can only help to the point of diagnosing that something *IS*
an electrical snafu.
> the south east in my 1990 V8...along the way, I tried to figure out the noise
> from under my dash....it doesn't matter what the climate control settings
> are, cruise on or off, what the radio is doing or anything else expect the
> speed and throttle position. The noise is rather high pitched, (almost
> electronic sounding), always stops when I declerate, it is worse when
> cruising at a constant speed. If I accelerate from the constant speed, it
> change pitch. The nosie seems worse at 65-70 versus slower or faster.