Solved it! Turns out a screw holding the heat shield on my intake had come loose. I had a friend drive the car with me outside of it to listen for the sound coming from the wheel well. It was less audible outside the car, so I opened the hood on a hunch and had him do the same thing. The noise...
I've done my fair bit of searching, and nothing has come up that describes this noise. The noise occurs from a stop or slow roll at RPMs below 1k, though it seems like it's growing above 1k RPM. No noise during normal driving. Does anyone have any insight?
Video Link: GTI Wheel Well Shudder...
I'm planning on taking out my aftermarket catback and putting the OEM one back on after hearing how snarly it is. The only thing that's bothering me is how ugly the OEM exhaust looks in comparison to anything aftermarket. I know there are Versus Engineering diffusers floating around that might...