Mewho

I think its the exhaust but not sure. Anyway, the noise sounds like a buzzing or rattling. If you had some piece of metal and placed it against something vibrating (like the frame of a lawnmower) it would probably reproduce the same sound. So far, I've only been able to reproduce the noise when the car is in motion.

Turning Japanese

Also, when did this start happening? Does is it happen at any particular time, such as when you are cornering hard, stopping abruptly, or accelerating quickly?

Mewho

So far I've noticed the buzzing during cornering and normal acceleration. The noise is somewhat intermittent as I cannot reproduce the noise on command.

Mewho

<center><img src="http://pictureposter.audiworld.com/13098/wierd_clip.jpg"></center><p>I've isolated the buzzing to the following conditions:

1) When car is in motion (makes a much smaller noise when not in motion...can barely hear it)

2) Occurs between 1900rpm and 2200 rpm

3) Can occur when both accelerating and decelarating

this may or maynot be connected to the noise but I found a weird looking clip on the ground where I usually park. Don't know if it came from my car or someone else's car. Looks something like the clip you see on the bottom of cheap swivel office chairs. I put a drawing of what it looks like above.

Turning Japanese

Look to see if the exhaust is loose anywhere. It may be rubbing up against the bottom of your car. Make sure it is secure and that there is enough clearance on all sides.