BMW Z4 E89 3.Oi 2011 - Water Ingress but no leaks

[flybobbie]

When I had my car key read by BMW dealer, they said the rear vents had been changed on call back.
Have yours been changed?

[wu_swordsman]

Yes, I have the green tab also to signify that this is the case. its worth noting that since my last post I have had no issue with water in the boot. The problem seems to be resolved. how....? I cant answer that but all is well.

[flybobbie]

People go on about the green tab, I think you will find it's an emergency fuel cap release.
When you take the rear right tail light off, a same coloured moulded plastic cable runs around from it to the fuel flap.

Would appear to be quite standard on other models.
I would have the key read.

[warmasice]

No they ruled this out when the boot was stripped, as did I as it happened the second time after using a garden hose also. Hence the jet wash when I got it back the other day...no water. I'm hoping just bad luck is at fault.

Have you had any issues since? I'm wondering if jetwashing the rear wheels/inside the arches contributed to the problem?

[dakargelb]

Dear All

Hi - I'm new to the forum and sad to say starting with a problem...

We've just taken delivery of a 35is after about 4.5 years running a 2.0is.

Anyhow, I was shocked to find quite a lot of water in the battery well and in a pool in that conical tubular hole in the foam to the right of the roof pump. I must have removed nearly half a litre so far. The water is clean and tasteless and possibly had some detergent in it as I noted slight foaming when wringing out the kitchen paper I've been using to mop it up.

It been raining really hard since the car arrived so I don't know if it is rain water getting through somewhere, or possibly its from being pressure cleaned by the garage we bought it from.

I have checked the carpets on both sides inside the cabin and both are perfectly dry. So I think the cabin is water-tight at least.

Looking in the battery well, there is no water staining or corrosion that I can see - so if I had to guess, I'd say it was recent water, rather than water that had been there for a long time.

I guess my first question is should I simply start by trying to remove all the water and checking it each day or do I need to go straight to a garage to have something replaced / cleaned - maybe a rubber seal, drain hole or vent (I've had a brief read of this thread)?

Kind Regards to All

[Stash36]

There's loads of threads on this very common problem.

Check rear light seals seated correctly. If the tool cubby hole is wet that is probably your left light seal.
Check air vents to left and right have been replaced.
After that it's trial and error, can be the third brake light or the main boot seals, which are very expensive.

Must admit I have solved this problem in the past but found boot flooded recently. I think it is something not fully understood such as water coming out of the roof when stored, or perhaps pressure washing.
The story the OP recites about BMW spending hours on it without a satisfactory answer is telling.

[warmasice]

Dear All

Hi - I'm new to the forum and sad to say starting with a problem...

We've just taken delivery of a 35is after about 4.5 years running a 2.0is.

Anyhow, I was shocked to find quite a lot of water in the battery well and in a pool in that conical tubular hole in the foam to the right of the roof pump. I must have removed nearly half a litre so far. The water is clean and tasteless and possibly had some detergent in it as I noted slight foaming when wringing out the kitchen paper I've been using to mop it up.

It been raining really hard since the car arrived so I don't know if it is rain water getting through somewhere, or possibly its from being pressure cleaned by the garage we bought it from.

I have checked the carpets on both sides inside the cabin and both are perfectly dry. So I think the cabin is water-tight at least.

Looking in the battery well, there is no water staining or corrosion that I can see - so if I had to guess, I'd say it was recent water, rather than water that had been there for a long time.

I guess my first question is should I simply start by trying to remove all the water and checking it each day or do I need to go straight to a garage to have something replaced / cleaned - maybe a rubber seal, drain hole or vent (I've had a brief read of this thread)?

Kind Regards to All

Change both rear light seals and bot vents. I'd start there.

[mcbutler]

I would be inclined to place an action camera or similar inside the boot with a light and run a hose for 20min turning the camera every 20min to cover the whole boot.
Or maybe a non permanent dye that will leave a trace inside the boot for you to follow
Or - dont judge me - do you have any small children/grandchildren lol

[dakargelb]

Thanks guys.

Regarding the light seals and vents, does anyone have the part numbers / a recommended supplier for these or do I need to head straight to the dealer?

I'm still getting water out - there's far more than I imagined.... <sigh >

(Oh, and the car is Black Sapphire, with red seats / aluminium trim.)

[Pondrew]

Thanks guys.

Regarding the light seals and vents, does anyone have the part numbers / a recommended supplier for these or do I need to head straight to the dealer?

I'm still getting water out - there's far more than I imagined.... <sigh >

(Oh, and the car is Black Sapphire, with red seats / aluminium trim.)

To be honest, if I were you I would dry it out thoroughly and see what happens before changing expensive parts which may not be the problem. As you eluded to in your first post, it could have been 'put there' recently by someone pressure washing it from underneath.

There are many useful threads on here about water in the boot of E89s. I would do a search and familiarise yourself with the likely problem before doing anything else.

[flybobbie]

Dry it out and then ring the boot with some kitchen tissue to see from which direction it's coming from.
Also check under either corner under the trim, that might be full and flowing over.
Few have had problems where the boot rubber trim runs across the back. Two rubber trim end bits with hex screws.

[clarker63]

Change both rear light seals and bot vents. I'd start there.

yup, the most likely cause of this, and the top boot seal also mentioned - see this thread..

viewtopic.php?t=115469&hilit=leak

[warmasice]

Thanks guys.

Regarding the light seals and vents, does anyone have the part numbers / a recommended supplier for these or do I need to head straight to the dealer?

I'm still getting water out - there's far more than I imagined.... <sigh >

(Oh, and the car is Black Sapphire, with red seats / aluminium trim.)

Get them from the dealer. Save yourself the time and headache. Change the seals and vents, they don't cost that much. Start there first.. see how you get on, then look at your boot seals after. Been there, done it!

[dakargelb]

Thanks for the continuing advice it is greatly appreciated. Still drying it out before I replace those seals or indeed try to trace how it's got in. I'm shocked by how much water I've removed - I'm guessing it was soaked up into the foam around the pump...

[warmasice]

Once you replace the vents and seals, you may still find water finds its way into the boot. It's actually the water in the chassis rails. Hard braking and sharp turns should get it all out over the course of a few days. You'll also want some of those pound shop moisture absorbing packs.. I put around 6 in to soak up any lingering moisture. Worked a treat and boot has been bone dry. I've posted a few thread/posts like a lot of others. Lots of useful advice on the forum.