Are these boot vents in good condition?

[q149]

My first post here on the forum, I recently bought a 6/2011 23i. Car is overall in great condition, however my journey with the Z4 started out with water in boot issues. The car previously had two leaking hydraulic springs replaced, but leaked oil still seemed to be around as it mixed up with the water that entered the boot. Pretty nasty stuff to clean up as you can imagine. Good news is: no damage done so far, no corrosion at all and everything functions as normal. May be I was lucky to have some oil in the boot to prevent corrosion

Thanks to all the great info on this forum and other Z-specialized forums I could diagnose the cause of the issues and solve two of them:

1/ Previous owner replaced both tail lights just before selling the car, but wasn't aware about the missing third bolt on new tail lights. Easy fix.
2/ The top seal with the two torx screws on each side was leaking. Not so easy to fix but seal is waterproof now.

I did a waterproof test today by pouring some liters of water on the rear window, even with the boot lid opened and all is well. Then I closed the boot lid and poured again lots of water all over the back of the car. Still good. Except for the two boot vents that make me worry a bit. After today's water test I noticed tiny drops of water that seem to enter at least one of the vents. Couldn't check the other one as it's hidden by the foam box with all kinds off electronics in it.

Now my big question is: is it normal to have even the least amount of water noticable in the vents from the inside of the boot? Or should they be 100% dry at the inside? I'm afraid that the amount of water leaking through the vent flaps increases the longer the car may sit in the rain.

Since it's a 2011 car, I presume it has the revised vents already from the factory. Please see picture to see what I mean.

Red arrows: tiny droplets of water that entered after today's water test.
Blue arrow: probably dried up water from before

watervent.jpg (186.92 KiB) Viewed 286 times

[flybobbie]

My boot been dry since bought 10 years ago. Those vents were a call back. I asked the dealer to check the key. He came back and said, boot vents replaced and new idrive screen fitted. This was back about 2011 when i bought the car.

My guess is that water that runs off around tail light finds it was to the rubber flaps and by capillary action finds it's way in.
Also roof down could be low pressure over car and reverse flow sucking in damp, flaps not sealing.

Mice and water, always finds a way in.

[q149]

A small update on this. Boot had completely dried out, so yesterday I made at trip of around 100 kms in the dry and when I came back everything was still 100% dry. I mean, no water appeared from under any of the bodywork rails.

Today I left the car outside in the rain all day long. When the rain had stopped I checked the boot: still 100% dry. This evening the sun came through and the road was dry, I did a short ride of about 10 kms. Immediately after, I checked the boot and to my surprise I found some small puddles of water in the little boot compartment at the driver's side (it's a EU car = passenger side in UK) where the vent is. The vent itself on that side remained completely dry, so it seems OK. Now I just don't understand where these small amounts of water keep coming from? The top seal is not the culprit, it was resealed and dry.

Any hints on this please? First picture (hard to see) is before I dried the new water drops/puddles. See my second picture after drying with a towel: you can still notice a drop in the corner, is this the water source?? Also when i slightly pressed the black grommit (circled in red) in picture 2 some water escaped from beneath it.

before drying, droplets/small puddles

PXL_20240610_190032710.PORTRAIT_kl.jpg (93.55 KiB) Viewed 133 times

after drying, still drop in the corner

PXL_20240610_192830625_kl.jpg (110.68 KiB) Viewed 133 times

[flybobbie]

Lay some kitchen paper or loo roll tissue around where it gets damp. See which direction it comes from.

[q149]

That's exactly what I started to do this evening. Also added some chalk marks on strategic spots. So far no more water, even after a day with heavy showers and a subsequent short drive. Due to work I didn't have the chance so far to drive while it's raining. Hope the bad weather will continue for some time