My passenger side floor is soaking wet do u no why?, it was raining realy bad last night but i can not see where it could have come in. the mat its self is not wet its just the carpet under the mat.

Sun roof ¿
wiper motor compartment
full of leaves
rust issues
door seals?

have you had the AC on by any chance ,if not then check the drain holes either side at the bottom of nwhere the wiper motor is as their are drain holes either side of the bulkhead or firewall in american ,to drain the floor just drill a 5/16th hole in the lowest point of the floor when the car sits in the kerb this will allow the water to escape i,old adage of mine if it can in then let it out

Hi,

This is of concern.....especially if no recent rain.

Your vehicle is covered by warranty and should be checked by your local BMW dealership.

If there has not been any rain, but your floor is wet....it's possible your heater radiator core (radiator) under the dash, is leaking.

Seek immediate attention.

Cheers,

what year is the vehicle, i have 97 marquise and when i bought the car the passenger floor was always wet after and during rain , i found the prolem let me know what ya got

shop vac the carpet dry then spray garden hose around both rear doors or around doors and see if you get wet or see a leak. Also spray under vehicle on both sides of car and check for leak.

I would say you have either a bad seal on the windshield or the seal on the passenger door opening.

Clean out the drain tube .

Have you by any chance jacked up the passenger side, or got vehicle on a hoist to make sure there isn't any plugs on the underside that may have fell out? They could be round or oval metal or rubber plugs, probably in that area.

I believe the problem is a leak in your heater core. The water would run down the inside of the firewall or near it thus running under the mat.

Is it antifreeeze from heater core or heater core hose leak?  Is the leak pure water, or maybe something else?
Put it in the garage again overnight with an old white towel in the drivers foot well, best if you can find a way to stretch it from drivers seat forwar to firewall and keep it off of floor mat.  Check it before you go to bed,  then in the morning if no leak found yet.  see if the color/location of the spot helps you identify the source.  I think the heater core is under the dash center.  Anti freeze is green/yellow or orange.
good luck