Thanks for the reply

did you ever get your engine mounts checked or throttle body changed/looked at?

 

I have a similar situation (17,C2, PDK). While in park or at a stop I hear a rattle (like loose marbles or gravel) and I feel a very slight engine stumble. If I put it in sport or sport+ the rattle and stumble is gone. I tried to pin point where the noise was coming from today. While in the cabin it sounds like its coming from the rear shelf on the drivers side. I checked for loose panels and did not find any. While outside of the car its very difficult to hear or feel the rattle and stumble. I hear it faintly in the drivers side wheel well. The car shifts and drives well. I was thinking motor mount or PDK related. Or it may be nothing and is normal. Very puzzling.

 

it may well be a pdk rattle, as I too used to hear them, after calibrating the pdk it seems to have disappeared. What I’ve noticed when there’s multiple issues, is we tend to think it’s once issue, only by working through it do we get to realise we had like 5 different issues, well I have anyway!

Do the following, I recently made a post

pdk calibration
throttle adaptation reset

will feel like a new car

 

Lol, I think it was the timing since it has teeth on the belt but it might be the serpentine, I need to check my receipt.

 

Never ask to get those looked at, but they replace the plenum under warranty because it wasn't closing properly.

 

These cars don't have timing belts...