Water in rear footwell of m5

[Skrambles]

Cleaning the car on the weekend, I found the carpet wet in the rear passenger side footwell.

Anyone had this on the f10? I think it's rain water rather than aircon. What's the fix and is it a warranty job?

Pretty annoyed about this given that the car has spent most of its life in the garage, and only been kept on the drive since last summer.

[d_a_n1979]

Skrambles said:

Cleaning the car on the weekend, I found the carpet wet in the rear passenger side footwell.

Anyone had this on the f10? I think it's rain water rather than aircon. What's the fix and is it a warranty job?

Pretty annoyed about this given that the car has spent most of its life in the garage, and only been kept on the drive since last summer.

Lots of info here:

https://forum.bmw5.co.uk/topic/116098-heavy-rain-w...

But it could also be the vapour barrier that’s failed in the door card; so check that first and re-seal if it has gone...

If not, it’ll more than likely be the fabled yellow grommet unfortunately

However, does your car have a sunroof? If so, check the drains etc

[Riggie]

Not a warranty job as the get out is 'weatherstrips and seals'. Most likely to be the yellow bulkhead grommet. I removed the acoustic cover from mine and lagged the thing with silicone. I left the cover off and all has been well since.

[Skrambles]

d_a_n1979 said:

Lots of info here:

https://forum.bmw5.co.uk/topic/116098-heavy-rain-w...

But it could also be the vapour barrier that’s failed in the door card; so check that first and re-seal if it has gone...

If not, it’ll more than likely be the fabled yellow grommet unfortunately

However, does your car have a sunroof? If so, check the drains etc

Thanks for the info. It does have a sunroof. Looks like poor design.

[Skrambles]

Riggie said:

Not a warranty job as the get out is 'weatherstrips and seals'. Most likely to be the yellow bulkhead grommet. I removed the acoustic cover from mine and lagged the thing with silicone. I left the cover off and all has been well since.

That's a pain. I'm not going to be stripping stuff down myself, so will see what BMW says.

[Don Phil]

Replicate heavy rain or wash the car again (blast the rear windows and doors at both sides), leave the car a little while, go back to it and open the driver side rear door first, see how much water comes out of the bottom. Then do the same with the passenger side door.

If it's the door vapour barrier you'll see a difference between the two results. Mine used to do it when it'd been bad weather, the rear passenger door used to gush water, the drivers side was fine.

[Skrambles]

Don Phil said:

Replicate heavy rain or wash the car again (blast the rear windows and doors at both sides), leave the car a little while, go back to it and open the driver side rear door first, see how much water comes out of the bottom. Then do the same with the passenger side door.

If it's the door vapour barrier you'll see a difference between the two results. Mine used to do it when it'd been bad weather, the rear passenger door used to gush water, the drivers side was fine.

Will do, thanks.

[Riggie]

Skrambles said:

Will do, thanks.

If the carpet is wet in the front nearside as well, it'll be the grommet, as water runs down the bulkhead and finds its' way to the rear footwell.

[Skrambles]

Riggie said:

If the carpet is wet in the front nearside as well, it'll be the grommet, as water runs down the bulkhead and finds its' way to the rear footwell.

It's just the rear, I think, but I'll check again in the morning when I do the water tests.

[E63eeeeee...]

The carpet in the front is on about four inches of foam which is why even though the water runs through from under the glovebox it's much more noticeable in the back. My front carpet seemed bone dry until I wedged the vax nozzle into the carpet gripper holes and water just kept coming out.

Shocking bit of design and about 50% of the reasons I got rid of my 550i. Much harder to do anything yourself with the bigger engines in the way too. I got mine done at a local indy, they did the yellow grommet and dried it out over a weekend. There was another in with the same problem out of four cars they had. When it started steaming up again I pulled the trigger on getting rid. Hope you get it sorted if you like the car but with that and the fuel pump problems I'd had enough.

[Skrambles]

E63eeeeee... said:

The carpet in the front is on about four inches of foam which is why even though the water runs through from under the glovebox it's much more noticeable in the back. My front carpet seemed bone dry until I wedged the vax nozzle into the carpet gripper holes and water just kept coming out.

Shocking bit of design and about 50% of the reasons I got rid of my 550i. Much harder to do anything yourself with the bigger engines in the way too. I got mine done at a local indy, they did the yellow grommet and dried it out over a weekend. There was another in with the same problem out of four cars they had. When it started steaming up again I pulled the trigger on getting rid. Hope you get it sorted if you like the car but with that and the fuel pump problems I'd had enough.

You were right! Went out to have a look this morning and, though the front passenger footwell carpet is dry, my outdoor vacuum pulled out some water through the gripper holes.

In the m5 engine bay, it's virtually impossible to see down to the drain (or whatever) behind the glove box. I could see there was pooling water there and vacuumed about 1/2 a litre out (with a few leaves). I tried pouring some clean water down to see if it drained and it just pooled again (though this may be partly due to the slight slope on the drive).

Seriously hacked off by this problem, especially when it seems to have been a problem for the 5 series as far back as the E39. Like you, it's got me 50% wanting to get rid of the car, just because I know it'll be a recurring problem.

Also makes me wonder - if they hadn't even managed to sort the issue by the time they designed the f10, would the f90 also be affected? Time will tell.

[bmwmike]

underbonnet drainage is different on the f90, and i dug out a video of an f90 being built and i dont think (iirc) the grommet is there.

BUT, they do apparently suffer the f10 door edge corrosion so BMW did carry that over at least !!

[Skrambles]

bmwmike said:

underbonnet drainage is different on the f90, and i dug out a video of an f90 being built and i dont think (iirc) the grommet is there.

BUT, they do apparently suffer the f10 door edge corrosion so BMW did carry that over at least !!

Good to know that there's some continuity then!

[E63eeeeee...]

Iirc what you can see isn't the same pool that's breaking through the grommet - that's trapped behind the grommet cover lower down and pretty much inaccessible to any kind of poking. It does suggest that all your drains are stuffed though - presumably a previous owner parked it under a tree a lot. Even once you've got this sorted you might want to think about clearing all your other drains before they start leaking into the cockpit or causing other problems.

I don't know about the F90. I believe they resolved this after the F10, but I decided that while BMWs make excellent fun cars I was never going to have another one as a main car that I need to be able to rely on.

[Skrambles]

E63eeeeee... said:

Iirc what you can see isn't the same pool that's breaking through the grommet - that's trapped behind the grommet cover lower down and pretty much inaccessible to any kind of poking. It does suggest that all your drains are stuffed though - presumably a previous owner parked it under a tree a lot. Even once you've got this sorted you might want to think about clearing all your other drains before they start leaking into the cockpit or causing other problems.

I don't know about the F90. I believe they resolved this after the F10, but I decided that while BMWs make excellent fun cars I was never going to have another one as a main car that I need to be able to rely on.

I'm the first and only owner (so far)! The car has led a very pampered life - first 7 years parked in a garage overnight. But, come to think of it, there is a massive tree over the car park at work and I have occasionally had to clean out tiny bits of tree-debris after parking the car at work.

I always thought it would be an engine problem that would make me get shot of the car - never imagined it would be the car drowning due to defective drainage!

[theboss]

Did you get to the bottom of it?

Just discovered I have the same problem with the drivers side rear footwell so I'm hoping this means its the rear door rather than the yellow grommet. Passenger side seems dry.

Whatever it is it seems like its going to need a thoroughly good dry out after fixing the root cause.

[Skrambles]

theboss said:

Did you get to the bottom of it?

Just discovered I have the same problem with the drivers side rear footwell so I'm hoping this means its the rear door rather than the yellow grommet. Passenger side seems dry.

Whatever it is it seems like its going to need a thoroughly good dry out after fixing the root cause.

Mine was the yellow grommet, but it's on the passenger side. Yours might be the door.

[Skrambles]

Sorry, meant to say that yours is most likely the door!

[theboss]

How did you get yours fixed as the grommet is inaccessible on the M5 compared to others - did you just give it to a dealer?

I'm wondering if I should get mine done preventatively if I'm going to go to the hassle of drying it all out.

[Skrambles]

theboss said:

How did you get yours fixed as the grommet is inaccessible on the M5 compared to others - did you just give it to a dealer?

I'm wondering if I should get mine done preventatively if I'm going to go to the hassle of drying it all out.

I took it to BMW. I couldn't even get close to the grommet. I would get it done before it becomes a problem - it will definitely happen, just a question of when and how much damage it does before you realise.

Mine's going back in because the water is building up again in the engine compartment when it should be draining away. I don't think they cleared the drainage channel when they replaced the grommet, but we'll see. Such a pain. I'm not 100% happy at the thought of what problems may be in store if the water has affected wiring.