Well my 00 GT has a weird rattling noise. Has had since I got it a couple of weeks ago. My 97 had kind of the same thing. Seems like it is coming from somewhere behind the center console, maybe down by the shifter...wife says it seems like it comes from around the ac vents. It only happens around 1800-2500 RPMs and only if I am giving it very light throttle maybe 1/8 to 1/4. If I get on it at all, it goes right away. If I have the car in neutral I can go under the hood and rev it up and nothing, sit in the car with it in neutral and nothing, or at least I can't make it do it when in neutral. Any ideas? It is kinda a rattle or a buzzing sound. Kind of like the frequency of that RPM range under light throttle is making something like a heat shield or loose bracket start making some noise? I have no idea. Thanks for any help!