[sparkie]

Not used the car for a while and jumped in it yesterday and could smell dampness.
Had a wee look today and passenger side floor is wet under the mat.
Ive looked above where it would be and around the fuse box area is dry n dusty so that would rule out from above...
Under neath the carpet inc the foam and insulation are bone dry, sides around the damp patch are dry.
I've put the hose over the car and still nothing... It's an isolated spot as though someone has poured a jug full into the middle where your feet would go. Suggestions please

Oh, car is E91 330i with paroramic sunroof...

[Brian mc21]

Take your door card off and make sure the membrane is still attached all the way round. This was the cause of my leak.

[MrPogle]

Mine too. Parked the car in the rain with some bog-roll draped along the bottom of the passenger door and it was obvious the water was coming from the back of the door card. Bought some butyl-tape to seal the membrane in place and the water ingress went away.