e46 water in rear footwell passenger side

[master garion 1]

Arrgh this is driving me nuts!! Does anyone know what could possibly be causing this? It's not the vapour barrier (redone with new barrier, proper bmw glue stuff and even replaced the door card clips) or door seals. Don't have a sunroof, don't have rear a/c vents. Hosing the car down does not show where it's coming in. I have noted some wetness in the battery compartment and some moisture behind the rear seat backs, particularly the bolsters on both sides, but I don't know if these are related.

Also, we're not talking about a little dampness in the carpet - it's absolutely soaking! There's gotta be like a litre or two in there.

Hoping the collective bimmersport brain trust might know what's up. Cheers

[allan 295]

Rear windscreen possibly

[Allanw 1051]

It could very easily be coming from the front - the rear floor is often just a touch lower.

[*Glenn* 854]

You will need to check all doors for damage to the vapour barriers and they must be sealed correctly. The trim clips must also have the black sealing washers on all clips. The rear foot wells are the lowest and under the carpet is foam. We have also struck the heater box drain pipe seal for the AC in the floor misaligned when work has been carried out on the heater or heater matrix.