For the past couple years I would get water only in my rear passenger foot well during the summer only on long trips. Now it's happening all the time. I checked my condensate drain and it seems clear. I disconnected the drain tube from floor drain valve and poured water down and it was fine. What else can it be?

 

Forgot to mention this only happens when the A/C is on. I have the A/C off all the time now and it hasn't happened since.

 

it is rear drains blockage. It has left and right sides. Rear bumper need to be removed to see the hose outlets that are located in both sides near the bumper tips.

To free the blocking, you can buy a flexible speedometer cable or find nylon cable that is long and stiff enough to insert into these 2 holes until you see the end comes out at the rear part of sunroof.

Rear bumper removal DIY
http://www.vaglinks.com/Docs/Audi/C5...perRemoval.pdf

 

thanks. I do have a sunroof but my water problem happens on sunny warm days when I'm running the a/c for a long time. It rained for 6 days straight last week (remnants of hurricane Lee) and I didn't get one drop of water in my car. This has got to be connected to a/c condensate drainage somehow.

 

the a/c drain is clogged up,
you need to clear the drain before anything, water goes under the carpet to the back of the front seat.