Everytime it rains heavily my A4 (1998) gets a major water leak inside the car. The driver side floor fills up with up to several inches of water. I'm starting to get worried about serious water damage.

At first I thought it was a bad seal between the lower windshield and engine compartment, but I sealed it and it's still happening. There is a great deal of water still getting into the engine compartment especially underneath the battery and brake pump. It must be getting into the interior some how.

Any ideas? It's driving me crazy.

 

sunroof drain plug. same thing happened to my car

 

Also make sure the battery plenum drains are clear. Water shouldnt builup in the battery plenum. Also check your ecm box. The seal where it meets the body can leak. Or if the top is cracked or not secured properly it can leak.

 

Thanks for the advice, it turned out the culprit was the battery plenum drain. It was visibly clogged with plant debris, I just removed by hand.

Although I'm not recomending it, I also took the liberty of drilling a 1/4" secondary drain just beneath and to the left of the battery.

I didnt have to do anything nearly as extensive as this article, but it was still helpful in showing the drain points: http://www.audipages.com/Tech_Articl...tordrains.html

Now to dry out the interior!