I was happy for a week
Kept checking the carpet, it was dry, even after a little rain, but it was not a proper test. Then I washed the car yesterday, in the sun. And afterwards the carpet was wet, with warm water!
So today in despair and frustration I started digging in to the footwell dismantling any easily accessible trims to see exactly where its coming in. As it happens, from a most unexpected place!
I dug into enough sound deadening to be able to see the metal of the firewall and the mating joint of the pedal box. Then I poured a bucket down the windscreen. And sure enough it came in, to the extreme far left, from up above in the corner. Up there somewhere there is not just a single sheet of metal of the aluminium body, but a double-walled section a bit like a gently arched horizontal duct. And in the left corner before this double walked section has a square cut-out at the bottom. Water was coming in, like an Alien
inside this duct and dropping in from above!
With the sound deadening pushed out of the way I could also see the other side of the grommets in the corner, there were stains just below the big grommet for the wiring loom, water had got in via that in the past but not any more. Probably from when the wheel arch drain was blocked, I often had standing water there, so watch out for that one, worth sealing I think.
But unfortunately for me I am still none the wiser where the entry point is for my water ingress. I also suspected the lower left coolant hose going to the heat exchanger. It has a white oval seal and the lower seal is looking worse for wear, I thought maybe this seal goes through this double-wall section and may be letting water in, but I found it from the inside and it is dry with no stains. Then I sprayed water directly at just the lower seal with a hose but nothing came in.
Here is the offending 'duct'
Who is the most knowledgeable D2 genius who can solve this mystery?
Zoomed out a bit
