A5 Convertible (2010) water in both front footwell

[JHB]

Hi all - I'm aware that there are several threads relating to this issue however none match our experience...

Car is Audi A5 (2009-2017 - B8F) Cabriolet / Convertible on a 2010 plate and RHD with 145,000 miles. 

We have owned it from new and has never had a replacement windscreen or major accident damage

Around 3 months ago we noticed a considerable amount of water in the drivers and passengers footwells. The drivers side was very (much more than passenger) wet and there was damp transferring back to the drivers side rear seat foot well.

- We thoroughly checked and confirmed it is not relating to Air Con or Heater Matrix.

- The volume of water increases whether parked or driving but only in wet weather.

- I don't think there are any drain points in the pair of locking points on the top stainless screen surround but would be good to know.

- We cleared all leaves and debris from the x2 rubber drain plugs in the Plenum Chamber, tested and they are free flowing. (instant and similar volumes of water from both - Passenger side to rear of engine, drivers side to rear of front wheel arch)

- We used 'Fly Mo' plastic line to check and clear the drain routes through the A pillar rubber. The larger drain on each side was plugged with dirt, but now cleared - it exits around 3/4 of the way down the A pillar above the triangular rubber sealing flap (see images)

- The tiny drain hole (is it a drain? see jpg 0329) in the bottom corner of the A pillar rubber extends only for around 200mm so may not be a drain hole.

- It is possible to feel under the triangular sealing flap (image 0332) and it is wet and very muddy / dirty underneath which surprised me as it looks as though it should seal from the exterior and be dray and fairly clean underneath.

- We found that the bonnet release catch (RHS of drivers footwell just forward of base of A Pillar)  would be dripping with water almost immediately after pouring water over the windscreen. 

- Additionally if we push / squeeze the A pillar stainless trim & door seal water further drips appeared on the bonnet release and below the rubber flap in the front of the door shut line.

On close inspection the stainless trim and the black seal to the windscreen appears loose (both sides of the car, but much worse on the drivers side) it rocks around and springs away from a good fit even when pushed back to original position.

I don't want to remove this trim but feel that this is probably the issue and that there must be cavities in the A pillar itself.

Currently I'm planning to seal (with black silicone) the black trim to the windscreen glass. This would confirm or otherwise I think and may well be a semi permanent repair without huge expense.

I would be very grateful for any other thoughts, advice or similar experience relating to this. Water ingress seems to be a very common problem so hopefully this helps and we can solve it for others! Thanks for reading.