Yes quite normal. Another fault is that the drain holes in the bottom of the door drain through a V-section door seal. This works when the door is open. but when closed the seal compresses and seals the two or three drain holes in the bottom of the door. If you are hosing or it is raining the water runs down the glass and into the door where it is supposed to run out of the bottom. I have been doing more homework on this as I am trying to sell my 02 Leon Cupra and whilst mine has never been bad there is seepage and as I have not been using it, it has developed a slightly damp niff. This
problem is not isolated to Seat it is a VW Group wide
problem and a design fault. The Golf suffers from it as does the Audi A3 and A4. I know as I have just bought an A4 Avant and the water collects between the seals here as well.
I have been Googling and phoning around and here a few extra tips. Spoke to a Car Trimming Company yesterday and they say to
help aleviate the
problem on Golfs, they install an aftermarket bodge of a polythene membrane between the door frame and the ancillaries panel. It is well known that the rain when entering the top of the door runs down the inside of the door skin and the back of the ancillaries panel, from new, rather than having a damp proof membrane there are seperate seals and plastic deflectors to keep water out of the speakers, window motors and other electrics. Old Fords always used to have a sheet of polythene. The second thing to do is to renew the foam seal around the rear of the ancillaries panel. Most of you seam to refer to this as sealing chord with a part number. My local Seat Stealer use something called stickaflex which their Body
shop buy in. Most Body shops seem to use a squirty panel sealer that is referred to in the superb
guide, but use the low odour one. I have just discovered a company "Sealsdirect.co.uk" that supply various different sealing extrusions, costed by the metre, which would be cheaper than the dealer.
So in summary, take the inside of the door off
Tape a poly membrane tot he rear of the panel, make sure it does not foul the window and locking mechanism
reseal the ancillaries carrrier panel to the door
modify the V-section seal to the bottom of all the doors this involves a stanley knife or nail scissors! cut a section out of the lower seal to allow water to drain through
Clean and dry out carpets and soundproofing
Get anice air freshener
Put car in a garage or under a car port!!!
Nominate the guy/girl who designed the door seals for VW for a Darwin Award for stupidity!