I have an '88 bonneville with 135,000 miles. ide say about 2 months ago, i started hearing a funny whistle sound coming from near my rear driver side tire. i put it up on a ramp and it is coming from that area, but i cant specify from exactly where. it only does this when my car is running, so that eliminated in my mind the air shocks. i dont think its my brakes or it would be leaking fluid, and my breaking has been fine. i also started getting 200 miles per tank instead of 300 when this whistle started. i didnt think the two symptoms were related till recently. could it be fuel fumes escaping from a line?, or a bad connection from the gas tank? any suggestions would be GREATLY appreciated.

Bobby from Vegas

i would think that there is a crack somewhere in the exhaust system that is causing the whistle. check for cracks in that.

fuel pumps whine espescially if the pickup it dirty although it may very well be a vacume leak or exhaust.

hi i have a 88 sse with only 78,649 original miles and i just had to change my fuel pump due to a loud whistle. i took a doctors stethascope and went under the car. when i put it on a certain spot on the gas tank it really hurt my ear it was so loud.. so i changed my fuel pump and never had that problem again.. its been about 2000 miles since i changed my fuel pump and it has not made that whistle again.. my car only whistled when i had 3 quarters of a tank or less...

thanks guys, i'll check it this weekend and get a response on here on monday. thanks again for the suggestions

Hey everyone,
Didnt get a chance to get under it, but I am pretty sure now it is coming from my break system. It definitely effects the whistle when I put more or less pressure on the break. And it only seems to whistle after the car has been running for a while. Could it be just a bad break line? Again, your guys help is greatly appreciated.
Bobby

When braking..your engine would be looking for less fuel.

You may want to check your fuel pressure before swapping the pump, even if the noise is the pump. I say this because GM pumps are known to be loud and whiny from the factory and tend to get louder with age. The noise doesn't necessarily mean the pump is bad. Although I have replaced pumps based on noise to nuts ratio. The noise was driving me nuts.

try a bottle of fuel injector cleaner and see if the noise changes after you run a tankful.

i'll run a bottle of feul injector cleaner through it and let everyone know.
again, the help is much appreciated