Two months ago, I came back to the car after being out of town for four days, to find condensation on the inside of the windshield and about half an inch of standing water in the rear driver side footwell. This happened out of nowhere, we had owned the car for eight months already without issue. There was also water in the front driver footwell, though somewhat less. None at all on the passenger side of the car. I towel dried it and then ran a dehumidifier inside of the car for a few days. Dealership that sold it to us CPO in January 2023 asked for $3400 to clear the drains. They wanted us to claim it on our insurance. We did not do that. A month ago, I finally had the time and dropped the headliner to clear out the sunroof drains myself. This seemed like the logical start, as the rear driver side drain didn't seem to be working correctly when tested with water. After clearing, I tested all four drains with water again and they were all clear.

Every few days, I feel around on the carpeting with my hand. Noticed dampness in the carpet again within a few days of clearing the drains. Figured it might still be from before, though I swear the carpet had felt dry a few days prior. From there, it seemed to dry out over a week again. Now I’m finding fully saturated carpeting in the driver footwell again. Seems like water has to be leaking into the car still. Can’t figure this out. The water has only been in the driver and rear drivers side footwells. Both passenger side footwells stayed dry through it all. Initially it seemed like the water was mostly in the rear footwell, but now it seems like it’s coming from the front of the car. Only finding water under the pedals. Carpet fully soaked under rubber weathertech liners, definitely not from wet shoes.

I wonder if it’s the AC condensate drain issue? The VIN shows no open recalls. I’ve made a point to not run the AC over the past couple of weeks just to eliminate that possibility. I've run the heat but turned the AC off when doing so. I figured without the AC running it would not generate condensate to leak into the cabin. Are there any other known leaky areas on these cars? Is it the window seals or doors? The headliner was never wet to the touch, which seemed odd for a sunroof leak. Neither was the trunk, though when I took out the trim and headliner to access the drain hoses, there was a tiny bit of trapped moisture. It was around the driver side C-pillar trim piece. That’s my only clue. Makes sense for that clogged drain, but doesn't make sense for no wetness on the floor of the trunk. Again, headliner was dry, even on the backside. Is it possible there’s a leak back there but that the water is somehow traveling to the front of the car under all the carpeting? Really out of ideas. The only other thing is that I did not add a hose clamp to the sunroof drain when I was in there. Hose seemed snug and no water was leaking when I tested with the headliner out. Still, I regret not doing that just to eliminate that possibility. Might tear back into it today to add clamps. If anyone has anything to add, I'd be very appreciative. Very frustrated by this car (its a 2020 with 16k miles on it currently) and by the dealerships handling of it.

 

Something is up with the drain hose. Did it come undone again?

A/C drains at the bottom of the car center and rare to see those come undone and clog

https://www.realoem.com/bmw/enUS/sho...diagId=64_2038

See number 9 and 10

https://www.ecstuning.com/b-genuine-...n/64119139887/



Check and make sure its ok. Its under the car, center near exhaust, and might be near that heat shield where it comes out.

https://www.realoem.com/bmw/enUS/sho...diagId=51_3240

Near number 2 somewhere.