I never use a car wash so I can't comment on that. Did you check the drains from the sun roof. I don't care whose car it is, if those drains plug, your taking a bath. Our Passat did it-garage kept. My father in laws Caddy- garage kept drives 4 miles a day, TOTAL, his drains were plugged. It's not any ones fault per say, just something to keep up on with a sun roof. The Caddy was packed with yellow pollen dust from trees. They just fill with whatever. There should be drains near the corners that you can blow air thru with an air compressor. Make sure you get a good seal, we put a little water in them then blew through the water. Now I better check ours!
Sent from my SGH-T989 using Tapatalk 2