Probably getting in under the seal along the top leading edges then running down inside the door trims so you don't see it and it dribbles out at the bottom into the footwell.

That's where mine was coming in from before I replaced the seals for new.

Stay in the car and get a mate to spray a hose over till you confirm.

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The door glass can be adjusted for fit

(though it's a fiddly process) and you can also raise the seals with a few well placed washers to better the contact.

You can also get the eccentric guide rods from Mr T themselves which pull the t-bars in tighter but I'd guess a bit of fiddling with the glass will sort it under the circumstances you've mentioned.

None of these will help your problem if the water is coming in under the seals though.

Also make sure your wet carpets aren't sweet to the taste.

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.if they are it's not water but coolant from a leaking heater matrix.

R.
