Ok So I am having a really wierd, almost vibration "rattle" under the hood. It does not make the noise while I am sitting still or am in Neutral, however in 1st and 2nd and the low end of 3rd gears I get this rattling noise coming from what seems to be near my floor board (driver's side).
I checked the engine bay, thinking it could be like a loos heat shield. I tightened everything up, but no luck. Is there a heat shield down under the driver's floor board?? I am really confused, especially cuz it only makes the noise when I am driving in those gears. Any ideas would be appreciated.

By the way its a 2000 A4 1.8Tq Manual

 

sounds transmision related

 

It doesn't sound like it though. It is definitely an exterior rattle. There is no vibration in the transmission and it is not coming from that area...But i will have a look around.

 

Check your exhaust mounts, and there are some heat shields up there. Just get under there and take a look.