My 8 started rattling about a week ago. It happens when I give it gas from idle. It sounds like it is coming from the right rear of the car. Is this something I should worry about? Should I take it in? It happens in gear and out.
When I give it gas quicly from idle, it rattles until about 2k RPM. If I ease the gas on, it doesn't happen. Anyone have this happen to them?
It sounds like it is coming from under the car.

 

It is very likely the heat shield over the muffler.

If you get under the back bumper plastic, you will see the huge muffler, sideways under the trunk - above it is a big rattly heat shield, that sags and touches the muffler 'can'.

Sounds awful, but it can be easily pryed up away from contact, or get the dealer to do it.

S

 

If it sounds raspy and metallic, it could be related to the damper recall / tsb. I had the raspy noise at around 3K (resonant frequency apparently at that RPM) and it went away after I had the damper recall work done.

 

What exhaust do you have? I would be checking into the muffler/exhaut situation first and the damper/tsb second. There are known issues with muffler/heat sheild type of rattles, search around here after looking underneath to see if there is any possiblity of touching/rubbing. Some have said this problem appears after heating up the exhaust which heats up the rubber hanger devices and causes expansion and contraction to the point of moving the muffler.

 

I've got an 05 and this sounds exactly like my issue, although it would sound like its more under engine compartment passenger side.

Reving up at around 3k rpm it sounds like an exhaust leak? Kind of a puttering. My breaks have also started to squeal.