Jim D

Thanks Chris, this is really helpful, my new A3 cabriolet has exactly the same problem and it's driving me mad. Can you give me more tips on where exactly these drain bungs are, I've had a good look under the wheel arches by the bumper and also inside the boot but I can't find them (not sure what they look like). If its as easy to fix as just cleaning the bungs I'll be very happy, if I can find them.

WestoR

HI Jim D
I have a water leak in my A3 Cabriolet it's on the left hand side looking into the boot it appears to be coming from the top of the wheel arch will need to get the rear quarter internal panel off I have just got small camera on a flexible lead to look at this area some have reported that there is a drain tube from the hood run off going through the wheel arch and running out onto the back of the plastic wheel arch lining ? I have the car covered at the moment as it lets water into the boot when it rains, did you get your issue solved as I cannot see any run off any where near the pumper on my car.

WestoR

On inspection of that side of the car there is the motor for the hood I put the camera up the side of this cavity which has very limited space and I could not see anything as I could not get the camera in the right position so I took my car into Audi as I could not work out how to get the panels off and did not want to cause any expensive damage they said they will charge £70 to diagnose the issue then let me know how much it would cost, got a phone call to go in to see them they confirmed I had a leak, but were unable to say how much it might cost as they now required £670 to strip all the boot area and rear of the car and then they would a better idea of how much it would cost, so not in a position of writing an open check so I took the car away, the only upside to this is that they did not charge me the £70.

I got hold of a full service manual for the Audi which covered removing the panels so that I could do the work myself, got the trim removed in less than 30 minuets to expose the area but you cannot see any thing at all it all enclosed the hood motor is also blocking the only access to the area as well.

So I turned my attention to the wheel arch which others have reported, removed the wheel and took off the wheel arch liner which had 12 screws holding it on at the top of the wheel arch there is indeed a drain for the hood which runs out onto the wheel arch cover, all this area was covered in derby this drain a flap valve in it which I assume is there to allow water out but not in this was all gummed up with sludge so this could be causing my problem, I also noticed that this drain was not sealed around the edges where it goes through the body work so could allow water to enter ? as it is rubber I am a bit wary about sealing it with silicone as it might with time effect the rubber, I am also going to look at the other side to see if a similar arrangement exists there, will keep you posted on my progress.

Vincent

The solution is really simple- up behind the rear bumper on the right hand side there's a drain bung: it's the type that's supposed to allow water to drip out but not let any back in. Don't ask me why but this keeps getting blocked with road dirt. If you flex it a bit the water runs out, but the best thing to do is pull it out and wash it.