Hello all,
I have water entering the passenger side foot well from under the dash. I have searched the forums and found a lot of this type of question. It is not clogged drains. I have checked them all (engine side under bat, and in with pollen filter. Its not sun roof drains). I do see as an issue is the plastic trim at the bottom of the front windshield is not sealed to the windshield. It can be lifted slightly forward and you can see right into the cabin filter box from the windshield side of the car (with the hood closed). Therefore in heavy down pours and long term rain the water flows right into the cabin filter box and the filter itself fills up and it overflows into the cabin. Now I have read a few posts like this but with no solution. There was a recommendation to silicone the plastic fitting to the glass. I had thought of that but do not like to do anything out of spec. Can anyone check to see if they can lift their plastic fitting from the lip of the front windshield? Please let me know if that is unusual and or if you have fixed this problem before. This is for an 04 A6 s-line. THANKS!!!!!!!!

 

it is most likely the guilty part, I was going to suggest yuo check that trim.
Not sure how to fix it but have someone look at it. if yuo have an Auto, yuo are taking the chnace to get your TCU wet and have more issues.

 

That was the exact problem for me, I ran a silicon bead and retested with a hose.
Dry out the inside before you get mold

 

Thanks Guys!!! That was it. I ran an internal bead under the lip and a sealer bead along the windshield. We had heavy downpours in CT yesterday and no sign of water in the ft well!!!! Thanks Again!!!!!!