I've researched this all afternoon on here. Water sits on the of side section of the carpet just under the off side rear light. Reading all threads I found most point to the vents behind the bumper. But I've noticed that the water was dripping from a white plastic plug which a screw fastened into. This screw is one of three that hold the plastic surround around the rear light. I undid them and cleaned all crap from behind the trim. I then used a small amount of silicon to cover the top white plug and I placed a small amount on the screw. I'm hoping that this will cure my leak. But if not I then intend to put new vents and new seals for the rear lights. Hope this will help some, but not all with any leaks in a coupe boot.
