Water in trunk/boot advice. Nearly bought car!

[silver50]

A good friend of mine has essentially bought a 2009 Z4 but has since discovered the car had water entering the boot/trunk.

I don't know great detail as in which side or area, only that seemingly it may only happen when driving. The rear lamps were a bit damp with condensation at bottom of them when I saw the car.

I have been searching the web and came across a single post about some kind of vent in the rear wheel well someone's dealer changed over for an updated part when their car was in for a service because apparently they can allow water in. The vent had something to do with cabin air pressure while opening.closing doors?

The car seems ok, but I just want to try and help him become aware of what might actually be the problem.

Any input appreciated.

[pvr]

Rear lights were regularly replaced due to water ingress.

[pvr]

Example:

viewtopic.php?f=23&t=82922&p=1227285&hi ... t#p1227285

and

viewtopic.php?f=45&t=80852&p=1192180&hi ... t#p1192180

[silver50]

Yes, I'd seen a fair bit about lamp ingress but thought it seemed more that water was getting into the lenses, not water coming into the boot/trunk itself? Can the problem make water enter the boot?

I had an indication the problem seemed to only be prevalent when driving, this is why I wondered if anyone else had heard of the modified vent of some sort in the wheel well area.

[dr_john]

If I had water collecting in the boot I don't think I would be looking for a vent to cure it. I would be looking to replace a faulty seal to stop the ingress in the first place.

I don't think it's a common problem, I've never had it in the 3 e89s that I've
owned, but then maybe on a 6 year old model it could happen.

[Maniac]

Look at seals around lights, around the boot lid rim, the vents (recall) and the small plastic storage box on the bottom left of the boot space.

I've had an occasional drip from the boot rim seal which was due to degraded sealant. Others have had a lot of water from there. There's a thread on here by me on this in the problems section.

Check for water damage around the battery and roof pump as well as electronics under the right hand side of the boot floor.

[silver50]

Look at seals around lights, around the boot lid rim, the vents (recall) and the small plastic storage box on the bottom left of the boot space.

I've had an occasional drip from the boot rim seal which was due to degraded sealant. Others have had a lot of water from there. There's a thread on here by me on this in the problems section.

Check for water damage around the battery and roof pump as well as electronics under the right hand side of the boot floor.

What do the "vents" consist of? The water has apparently been at the battery/roof pump side. I am still suspecting them because it seems the problem couldn't be replicated with washing/hosing- it seems to only happen when driving in the wet. I'm not sure if the car has much of a BMW service history so am guessing if not, it may not have had the vents changed.

There is another issue which has come to light that seems to be the low pressure fuel pump (Car is a 23i 2.5) is intermittantly noisey. I can see it's an E89 foible. Annoying but not necessarily problemantic, but would be quite expensive to fix.

[flybobbie]

Don't think there is anyway water coming through vents could get to the part where the pump is.
My guess from my experience and others here that it's either
1/ Badly fitted seals at the back of the lamps, as they seal water from the boot.
Water entering here can get into the middle and side "sumps".
The water in the lamps is a separate issue, what I have seen that doesn't go into boot, my "sumps" have been dry.
https://www.youtube.com/watch?v=wHJa6z6e-a0
Watch my video and you will see the seals.
2/ Someone here picked up on the boot seal strip near the hinge, bit with two screws holding down.
3/ Also make sure the boot is flush with the body work, my boot was raised slightly, which I adjusted down and have seen other poorly adjusted boots.

Your best friend is kitchen tissue, strip out trim and lay around to provide a witness mark as to were it might be coming in.

[silver50]

Many thanks

I see the rubber seals. I imagine my reading last night about using a sealer was maybe around those rubbers. Couldn't see the back of your tail lights but normally cars have a seal right round the edge of a lamp tight against the body. Not a seal round a hole into the body...?

[flybobbie]

There are two seals, one inside the lamp, which leaks water into lamp and the two oval seals, which seal water out of the boot.
All in all totally bonkers design.