Boot door full of water

[Simon Wallwork]

This is a pain-in-the-ass!

What happened to me is that every single time I returned to the car after it had been out in the rain and lifted up the boot door to put my stuff in, three or four (or more!) pints of water came pouring out the bottom of the boot door.

The angle it was parked at seemed to be a factor.

I've been looking for another car for a while and at least one of those I looked at had the same issue.

Some helpful previous owner of my car had taken out the two trim screws holding the boot door liner in place at each bottom corner. This allowed the water out, but I'll bet there are loads of cars suffering from the same issue and it's just sloshing quietly around in there? -or not?:Confused:

My own car had recently had the boot door lock changed-no doubt due to the water ingress (not cheap!) and the 2001 A8 I looked at whose boot door was full of water, needed a new boot lock as it's had failed too.. Prolly worth checking if yours is watertight esp. if you keep it outside.

Anyway, I tried everything to fix it, mainly concentrating on the area where the rear number plate holder fixes in. The rear light clusters got a lot of attention too. I suspected the replacing of the boot lock might have not been done properly so I spent ages checking this out. Some of the threads in the five bosses that the screws go into on the number plate panel were stripped. So I built these up and retapped them and carefully sealed up any likely holes

Also the frozen water had seperated the boot door skin, along the top seam where it meets the bonded in ally piece that forms the rebated area where the rear number plate goes, so I had to fix that and seal it, and double-double check it as it seemed most likely to be the root of the problem. But still it leaked.

This went on for months- the actual boot was dry but the water always poured out when I opened the boot door, wetting the boot carpet.

I'll spare you all the investigative details, but it turned out to be the cable grommet located at the o/s front corner of the boot door. This had perished (although strangely the one on the n/s was ok.)

I got it with some RTV and the boot's been dry ever since.+++:love:

[IT]

Thanks Simon for that info - I've almost always had the 8's outside, but never seen that problem. I was feeling really stumped reading that, thankfully it was a solution you were posting and not a cry for help +++

[HPsauce]

Interesting; found this doing a search as I'm having a similar problem.
After rain, when opening the boot water pours out and into the boot - where I have a full-size waterproof mat/tray so it's not a big issue as I can mop it up quickly without further damage.

If I open the lid very slowly it's obvious the water is collecting at the very bottom/back below the numberplate and lights. As you lift and the rear of the lid reaches vertical it then runs forward inside and pours out in the corner around the edge of the inner trim panel.
If you just open the boot quickly that all pours straight into the boot; slowly and it mostly goes into the drainage channel just outside.

Looking around carefully I'm mystified as to where and how it's getting in there. Any thoughts anyone?

At the very bottom of the boot lid clear of the trim panel, in both corners, are little grommets. I've taken these out to see if they let it drain away.

Edit: Just reread and noted this: it turned out to be the cable grommet located at the o/s front corner of the boot door. and on checking again, I can now see that mine (the air tube one) is also not in the best condition. And looking at the geometry it's exposed, especially in driving rain which I went through plenty of yesterday.

Also, I don't know if this is a side-effect, but my alarm "chirp" has stopped on locking, so maybe the boot lock is suffering from the damp. :(

[mannyo]

My D2 was the same, you can stop the water building up easily. Open the boot and look along the bottom, there are two grommets (one on each end). I removed these, and this lets the water straight through until you sort the other grommet.

[HPsauce]

Yes, done that. ;)At the very bottom of the boot lid clear of the trim panel, in both corners, are little grommets. I've taken these out to see if they let it drain away.

I think I've got a tube of black mastic-type gunk somewhere. Just need a dry day to use it. :ROFL:

[Oli18]

Hi,

Not sure if this helps given that you seem to have worked out the issue but in case you haven't, when i got my very first D2 (Santorin Blue 3.7 QS), the NSR lighting cluster on the boot lid panel itself was slightly misaligned allowing water to get in. I use to get water coming out from the NS light cluster panel (the one inside the boot lid itself) as i opened it.

I fixed it by re-adjusting the light cluster.

Anyways, may also be worth a check. Hope you get it sorted! +++

Oli

[HPsauce]

Thanks for the info. +++
The grommet around the central locking air pipe is perished and DEFINITELY not a good seal, so I'll do that first than see what it's like.
I had that grommet go on my PF S8 as well, so I know one method of replacing it that works. From the factory it's moulded onto the pipe but made of a less durable material (why :Confused: )and breaks up (and peels off) easily.
I'll peel it all off and fit a suitable sized grommet/cap, cut to fit round the pipe, then finish and seal with suitable "gunk".

[HPsauce]

there are two grommets
Looking again I found a small rectangular grommet in the centre which is "lower" with the boot shut, so I've taken that out and replaced the round ones in the corners.
It's only about 10mm by 4mm but should be more than adequate as a drainage hole. :cool:

On the down side my bloody scuttle drain is blocked again. :mad:

Picture attached of the hole in the centre close to the boot latch, with plug removed:

[HPsauce]

The water is still getting into the boot lid somehow and I've no idea where. :angry3:

The grommet around the air pipe has now been sealed and anyway I haven't been driving anywhere in the rain for a while (surprisingly!). I put the 3 grommets along the bottom edge back at the same time though.

The boot lid was definitely dry the other day, yet when I opened it earlier today water came out, not masses, but some. Since I was certain it was dry it's been sitting out in the rain, but not moving.

As a short-term remedy I've taken the small rectangular grommet near the latch out again.

The only places I can think it's getting in is around the edges of the light cluster(s) or the numberplate surround, but there's hardly much water flowing round there even in heavy rain.

Any thoughts people?

[Simon Wallwork]

Are you sure the repair to the grommet nearest the rear windscreen, on the off side, is good?

I tried absolutely everything imaginable before tracing the fault to that one grommet.

[HPsauce]

Well I think so, but I'll reseal it again when we get some warm dry weather.

Just looked now and there's still some water getting in somewhere. Though I still have the rectangular grommet out so not much can accumulate.

[David's8]

Are you sure the repair to the grommet nearest the rear windscreen, on the off side, is good?

I tried absolutely everything imaginable before tracing the fault to that one grommet.

My boot lid fills up regularly and its one of the spring/summer jobs i need to get around to. I my case - and having followed this subject for a while - the cause appears to be the perished grommet. But I have to say I am not sure how the amount of water that gets in the lid (a good 1/2 pint) manages to pass upwards through the grommet. :Confused:

[HPsauce]

I've just been looking at that again, and literally SMOTHERING the entry hole, grommet and pipe with mastic.
I reckon it's the geometry of the roofline and drainage channel; it's seemingly designed that rain swept off the roof is caught by the leading edge of the boot and is supposed to go downwards and exit via the channels either side of the boot lid.
As such it's likely that a lot of water will hit that precise area. :(

[HPsauce]

:angry2: Just opened my boot and water poured out as it got vertical!

The cable grommets are both VERY well sealed. :Confused:

At the bottom edge the central rectangular grommet is open, the round ones at each corner are in place. I popped them out and both were wet behind.

So water is getting in somehow and accumulating at the rear lower edge, limited as I have the central grommet missing.

Look as hard and logically as I can I can't think realistically how.

One possibility is that rain is somehow coming in under the front edge between the rubber seal and the lid, then working up inside the lid. But I would then expect to see water in the boot, and there's none.

The only other area is around the lights and numberplate, but again it all looks well-sealed and could only be rain trickling in while parked.

[bobbygd]

Easy way is to get some clear silicone and go round all the bolts on the lights and make sure you do the strip that holds the number plate lights as well, Take the nuts off and put some goo on then put the nuts back on. 2 years running and mine is still dry.

[HPsauce]

Old thread but I had some useful input on this at Audi In The Park last weekend. :cool:
Talking to someone with a D2 (not sure who, not a regular here, but uses our sponsors a fair bit if I'm recalling the right person) who said he solved his problem by sealing around the numberplate mounting panel.

He spent ages trying to trace the source of the leak and eventually worked out that rain was running down the back of the boot lid and in the top edge of the numberplate recess surround.
He just filled it all the way round with mastic - very neatly as I didn't even notice until he pointed it out - but I'd rather do it "properly".

Mine is still a bit of an annoyance. Anyone know how that area is dismantled so that it can be reseated and sealed correctly?

[moltuae]

When the boot lid of one of my previous D2 '8s kept filling with rain water, some years ago, the cause was a perished light-cluster seal, though I can imagine how a badly sealing numberplate surround could cause the same issue. In my case, I fixed it my removing the light cluster and fitting a new seal.

[HPsauce]

I'm pretty sure I've eliminated the light clusters and cable grommets, hence the question about the numberplate surround.

[HPsauce]

... someone with a D2 (not sure who, not a regular here, but uses our sponsors a fair bit if I'm recalling the right person) who said he solved his problem by sealing around the numberplate mounting panel.

................. Anyone know how that area is dismantled so that it can be reseated and sealed correctly?

I'm hoping to look at this in the next few days, so before I "dive in" can anyone offer any practical experience of dismantling this area of the boot lid?
(I've had the lining off several times so know that process, but is that required?)

[johnny_quattro]

What with the recent inclement weather including some rather torrential downpours, I've been welcomed by at least a pint of water when opening the boot of my A8L. Those of you in-the-know will suspect that loud amplified stereo equipment of the conical variety may have something to do with it. My sub seems to be capable of not only rattling the windscreen wipers but also makes the boot and especially the number plate holder area vibrate.

I have already had to replace both inner rear light lenses and the current ones are cracked, but only on the reversing light part - the red part seems unaffected. I will also be checking the grommets and attacking them with sealant. The situation is so bad that I've had to take the furry access covers off of the inside lights in order to drain the water out, which happens automagically when I lift the boot lid up. Thanks to all prior posters on this thread for their useful contributions.

Since the sound pressure level inside my car is so great and I don't have the ski hatch access, I'm very tempted to removal the plate behind the car's rear armrests in a Tetley attempt at letting the flavour flood out... I'd be interested to know if this has been attempted before?

[diplomat2.6]

I've had this issue too. I really is hard to understand why quite so much water gathers in the boot. I could understand a cupful, but at its worst, I think I would be looking at nearly 2 litres.
If you wanted 2 litres of water in the boot lid, I don't think any method you could choose would be nearly as effective as one that circumstance creates on the A8 D2!
Can you still buy the grommets?

[HPsauce]

Grommets are moulded onto the tubing. :(
(Edit: Can be split/peeled off so maybe it's just glued)

[paulrstaylor]

Had this issue with my S4, was the cable gromit to blame as it enters the boot lid. Resealed that and all dry +++

[johnny_quattro]

Thanks all for the info. I will attempt to seal this before our next torrential downpour.

[27litres]

My boot grommets aren't in particularly good shape, but my boot isn't leaking (yet).
So I've just bought some of this (https://sugru.com/about) to experiment with!

[HPsauce]

I just used some (Sugru) on one of my grommets, see this thread: http://forum.a8parts.co.uk/showthread.php?t=11483 ;)

[Simon Wallwork]

Thinking this through a little, I wonder if the boot interior is actually at a little bit of low pressure, due to the A8 aerodynamics?

It's quite possible that a low pressure area forms behind the car at speed, causing air inside the boot to leak out- lowering the pressure within the boot and sucking water in through any available wet area.

I know mine was the grommet under the leading edge of the boot door, but why water would choose to go uphill into the boot door, when it could go down into the gutter is less clear.