I need help- I've got a 2011 tC; I put aftermarket LED taillights on it and it has squeaked ever since. I did this about 6 months ago. It took me awhile to figure out what it was but I figured out it is my rear bumper. The bolts in the wheel well are plenty tight, and it seems as though the screws between the tail lights are as well but they also seem like that are missing whatever it is they are trying to connect to; they will just keep turning if I keep turning them. It seems like there is not enough support on the back of the car to hold the bumper up. The noise can be made my putting the hand on the bottom of the bumper and pulling up and pushing down. My guess is the tail lights are a fraction of an inch too small to occupy the space. Any ideas? Fixes?