Did you do any mods to the car. Some times when you do it changes things. I had a noise coming from under the hood. It was a seal that was not placed right, so air was going between the hood when I was driving. It is fixed now and no more noise. Check all of your seals and wheather stripping. Another place you can check is the air filter assembly. Believe it or not if it is not put together tightly air will go through and make a whistling noise. It happened in my brothers Camaro Z28, and it sounded like it was coming from the rear as well.
First off, does it happen only when it is running, or do you have to be moving under 30 mph??????
This could be a clue.
Also, I didnt know if it is a manual or auto, but attempt to coast down from 40, and see exactly where the noise comes in, speed wise. Just slide the car into neutral, and see what you have, as when you put it in neutral, you take most of the driveline out of the picture, so you are basically seeing if the differential area is where the noise is located.
Best to you, c4c5
Ok, does the pitch of the whine change with engine rpm????
As your car is reved, does the pitch rise?????
Also, does it change, depending on what gear you are in?????
Please let us know, I have an idea, c4c5
Well, first thing is I would check your transmission fluid, as it is underneath the car, at the 22mm plug, located on the driver side of the pan.
The fluid must be checked when the temperature is between 80 and 125 degrees on the transmission temperature readout.
It should just dribble out of the hole.
Also, look to see if the fluid is aerated, or there are bubbles in the fluid.
Let us know, c4c5
If this is a whistling-hiss you hear coming from behind and below the driver that can be heard then the car is stopped or is at low speeds with the windows up, being that the car's a 97; I'd guess the car has the fuel pump noise problem.
If it is in fact, pump noise, it's not a problem from a technical sense but it can be an annoyance to some.
As is stated elsewhere, there was a TSB fix for this.