Coupe wet boot / water leak

[mj2k]

Hi folks,

Having repurchased my Z4C from the chap I sold it to, I've noticed it has a lot if condensation forming after I lock it up.

It has spent the last 4 weeks on my drive as been using the company car with all the recent fine weather! I looked deeper into the boot today & found my battery sitting in a pool of liquid, which having soaked up with towels I established was water not battery acid as my hands were not stinging!

I've pulled all the carpets out & dried them out. There was a puddle if water in the rear right hand side of the boot well, effectively under where the storage nets are. The grey padding around the suspension turret was also soaked through. All dried out now over the course of a few hours with towels & hair dryer but wondering how / where this was happening.

Trawling the search function brings up a lot of roadsters with wet boots, but only this one for a coupe: http://www.z4-forum.com/forum/viewtopic.php?t=44231#p635702

Never heard anyone mention these vents before or after this post.

Now it may be that the previous owner had a bottle if water leak there, but unlikely.

Given it has been parked up with all this heavy rain I'm hoping it was special circumstances, or could it be the rear window rubbers need replacing?! I now have dry towel in the right hand well to see if it returns.

Any pointers greatly appreciated, ideally aside from reversing up my drive as I would need to get out on the grass!

Cheers

Matt


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[srhutch]

If you have left the carpets out you could apply some talc. This will show you the path of the water and where it's coming from. I would think those vents are a likely cause. you should be able to see them from the inside of the boot. If it is them it's not hard to remove the bumper to replace. them.

 

[mj2k]

Car is with Grosvenor for bushes & 4 wheel alignment a week Tues, so might just be extremely lazy & pay to solve it!

Talc is a good idea, will have a look when light


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[mj2k]

100% it's the vent! had a great heads up from Paul on PM & checked it tonight, at least I know what caused it!


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[Taz]

so where are these vents?

 

[2dogs]

so where are these vents?

+1

 

[Stug]

so where are these vents?

+1

+2

 

[srhutch]

Behind the bumper, you can see them here on mine on the outer edges

 

[mj2k]

Behind the bumper, you can see them here on mine on the outer edges

That's them!

You can see them from the inside of the boot when the side carpet is removed, just below and towards the outside of the light clusters.

Did a test check on mine & it's not water coming through the rubber vent, but around the foam seal joining it to the car. Mine was sitting about 1/8" low on the leaking side, no idea if it was the cause but will get them changed - currently got carpets not fitted & a cloth there which I keep checking regularly as paranoid.

Will take some photos and post them up at the weekend as despite pulling carpet out 1st time I owned it to install the intravee, I hadn't even noticed them there.

Matt


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[mj2k]

Here is a photo from inside the boot with carpet removed. The wire above the vent is going to the rear lights, for orientation.

Mine wasn't coming through the rubber flaps, but around the seal at the top. It was sitting slightly lower than in the picture, but moved it up & all seems to be fine...think I will get them changed anyway as standing with a hair dryer in the boot is not enjoyable!

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[MHZ4C]

Very useful to know, thanks for posting mj2k.

 

[Taz]

Very useful to know, thanks for posting mj2k.

agree

 

[jaRED]

Well worth knowing, thank you

 

[mj2k]

To update, despite all the heavy rain & 2 watering cans to test I haven't had a drop of water in the boot after repositioning the vent correctly.

No idea how it could be dislodged, but positive to have stopped the ingress of water.

Will update after chatting to Grosvenor on Tues.

Matt


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[Taz]

 

[mj2k]

Part is B64.22.6.909.340 £9.32 for the pair from BMW, thanks to Paul478 for the details.

Grosvenor have it currently, having front & rear bushes changed & geometry alignment. The vents are 1.5 hours of labour as bumper needs to be removed.

Expensive day for me, but hoping car feels great again as presently all over the place, tramlining, non responsive etc.

Matt

 

[mj2k]

Grrrr BMW sent the wrong vent, so will be taking it back into Grosvenor on Thursday.

Car feels epic having had the bushes done, if your steering is sloppy well worth the investment!

 

[Dale_B]

Pleased I found this thread, I have just discovered my battery tray area has a small amount of water present.

Everyone seems confident these vents are the culprit. People who have replaced these, has this defiantly resolved the issue?

Rear bumper off job to replace them?

 

[mj2k]

Hi Dale,

100% cured mine.

Specialist informed me it was a bumper off job.

Matt


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[Dale_B]

Cheers for the confirmation Matt

Will look into getting this sorted.