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Both my driver front and back carpets get wet after a heavy rain. This doesn't happen on the passenger side. Does anyone have ideas about likely causes?

Thanks! Mike

Sunroof. But you may have two sunroof problems. Make sure the front drains are clear, run something soft, but firm down them and check with lots of water. They can be slow, but drain, but cause problems. Next make sure the back of your sunroof is well adjusted, spec is the back is 1MM higher than the roof, it doesn't have to be perfect, but it needs to more or less be adjusted. Yes there are rear drains, yes they should take care of it, but it seems if the sunroof is out of adjustment far enough it overwhelms the drains. Typically the rear footwell gets wet if the sunroof is out of adjustment and the front if the front drains are plugged.

If you could see them under the headliner, the holes in the front of the sunroof inset are the inside(s) of two welded tubes. They are short, with a long vinyl tube clamped around them. Those tubes run down the pillars on each side of the wind screen.

Two more of the same set up are in the rear, but their access is so restricted without major fooling around, it's probably about ignoring them.

The front tubes are close to the diameter of the drain holes. Turns out the sunroof seal and fit were never designed to be water tight. Only highly resistant, enough to allow the drains to handle the leakage.

Which they can't, if full of old dead leaves, dirt, and hardware from somebody fixing the sunroof. The trick is to use a heavy nylon line, like from a weed whacker, or a long wire ( filed or sanded smooth on the end to not gouge the inside of the vinyl tube ). That and some controlled flow of water to eventually see it's flowing freely on the ground.

If the line or wire can't clear the (little screws jammed in the silt), you're into taking the panels off the pillars and the tubes off the steel tubes.

Another source to check is the trunk gasket. Water can make its way in over the tail light assembly, across the trunk floor under the back seat, and make the back foot wells into wading pools.

How's your windshield seal?

Wow. If there is a seal, the problem is bigger than a leak.

Both my front windshield and rear glass used to leak before I had them redone. I don't have a sunroof.

I suspect that I also had a leak where the tail light seals go over the weld seam on the body of the car.

Thanks for all of the great information. I will track these things down. Best, Mike

Well, my sunroof appears to be the main culprit. I used some stiff line and cleared the front drain holes. Now I see water coming out of the rocker panels from 2 or 3 little holes on each side. I couldn't get to drains in the back. My sunroof seal and sunroof adjustment are so poor that it doesn't appear the drains can keep up. I had my son spray the roof and I could watch the water come into the cabin. Since my sunroof motor is shot, I am going to do the redneck sealing-up of the sunroof with some clear silicon and be done with it.

Removing the sunroof is not a big intellectual challenge. You may be able to Google search the procedure here from past posts or look it up on the BMW repair site.

Like this: Open the roof enough to get your fingers between the front edge of the headliner panel and the frame. Pull down smartly with both hands across the front. The clip pins will pop out of the frame and allow the headliner panel to slide back.

Once out of the way you'll see the two triangle brackets, three little hex nuts on each one. Take those off and the lid will come off.

New seal trim is available (realoem.com), a dab spendy but so will be removing silicone, in hours spent.

It's not that hard to remove a few screws to see behind the windscreen pillars to check drain tube is connected as designed. From my doing the above, it's not an hour to get things apart.