Porsche Enthusiasts Club Forum

OK, so this has gone on long enough, I have mentioned in a few places on the forum, but since I have had my 944 it has suffered from a wet passenger rear footwell.

Now, I have spent some time checking the usual places, including the following:

Sunroof seal (this was replaced before I bought the car)
Sunroof drains - running clear, no cracks
Fuel filler drain - this was detatched, I have rejoined and it is not draining OK
Hatch seal - this does leak some water over the drivers side rear seat, but only if water is sprayed at it from a hose
Tail lights - these were leaking a touch, so I have resealed
Hatch latch seals - these are leaking, I need to replace these
Blower cowling - this was leaking where it was cracked and deformed, I have repaired, reattached with foam tape and siliconed any areas where it is deformed along the top edge
Blower unit - I have removed this, cleaned and resealed

Now, the water does not seem to be getting the front carpet wet, is only on the passenger side, and runs from the box section just in front of the seat mounting point.

I have borrowed a pic from someone who had the same problem, but never resolved it as far as I can tell (his was drivers side, mine is passenger):



Mine appears from the arrowed area just behind where the box section meets in the inner sill.

After persistant rain (say all night), I will have water sitting in the footwell where it has ran from this point. It is not loads at one time, but when the carpets are down it will get to the point where it soaks through.

Since I have done all of the above it still seems to be getting in through from the bulkhead area. I have ran water all over the car, and although difficult to pin point as it takes a while before the water appears - it definitely seems to come from the bulkhead area.

Today I ran 10L of water over the lower passenger windscreen area and some time later I had a small amount of water appearing from the box section as above.

Other than what I have been through, does anyone have any ideas on this? It is possible the seam sealant in cracked along the bulkhead somewhere, but I haven't found anything obvious, and I can't see it running in anywhere along the firewall.

For anyone that has the carpet stripped out, or knows the body structure of these cars well, is there anywhere that water could run into this box section area, without running down the firewall or getting the front carpet/floor wet?

I have checked the inner sill and can see no obvious signs of water gathering in here. The side carpets are not wet either (I have read that some people have had water running into the cabin from the bulhead drains, where the seam sealer has failed along the inner wing).

I will carry on with this over the weekend, but so far I have spent a long time and found a number of minor leaks, just not the right one yet!!

Any suggestions appreciated

Hi Andy, I know you have checked the sunroof drains, but I came across this on a USA forum...

Solved!!! The sunroof drain hose(rubber) was partially disconnected from the steel coupler pipe in the dash/left pillar area. Simple fix! I removed the driver side pillar trim to gain access to this area.

Now I checked against the PET and it seems that the drain tube is in two pieces:

So perhaps having a look at that might help?

The box section that the seat mounts on is open inside the inner sill, have you removed the rubber bung close to it and poked your borescope around to see inside there? The inner sill section goes through to the front wheel arch, have you removed the liner to check the wing is sealed along the bulkhead? That is where the top bulkhead panel drains out too, if there was a breach there then water could enter the inner sill and come out as you have described..just a thought.

Remember that the inner sill has two compartments:

Hope that helps a bit..

Will it get more or less wet if parked on a set side? Is it front low or high?

1/4 glass maybe.

However you mention it got wet after wetting the windscreen? If it was front foot well I would say windscreen but its in the rear.

Do you keep your rear seats up or down? With the seats down if sun roof leaks it normally fully on to the seats back. I replaced my new sunroof seal for my old one as new one would leak....

A leak in the rear can run under the boot carpet and along under seats. Is the upright carpet damp or just the floor

The rear sunroof drains, have u tested theses with the floor all ready dry? Could be the hose has broken or came away under the headline

From quite thorough testing, dry floor, pour water in an area and leave for half hour, the only place it seemed to come in from was when I poured water along the bulkhead/lower windscreen area.

I had the a-pillar trim out along the passenger side and ran water down from the sunroof, I didn't see any leaking from the hose, or around the side of the dash.

Removing the wing liner is a good idea though, I will have a look in there.

As for ingress from rear windows or rear sunroof, again, I have checked, but also, the water only ever comes from the front of the car - I have watched it flow - appearing from just behind the box section in front of the seat mounting points. It will ten run from there and gather in the rear footwell, but it comes from the front of the car.

As for a certain side up, it did seem to be worse with nose up, but it is also running in (but less so) when the car is parked on the flat.

I have had the bungs out on the inner sill and looked in there for water, but couldn't see anything. It is quite a deep section so would really have to be filling up to transfer from there into the box section area. That or running along from further forward, but again, this would be capillary action and probably only a very small amount of water.

I think the other guy that had this problem on the internet ended up sealing up the box section to floorplan seams, but I'd rather not do this, I want to know where it is getting in from!

Are your sill drain holes clear? Wings/ blukhead outlet clear? Sounds like your confirmed what's happening just a question off how and why. If water was trapped once it made its self level with the outlet any extra water will run straight in to outlet. By been nose high outlet would be lower and require less fill before it starts to show as a leak.

Wonder if it running in where some wiring MIT run

What a horrible situation

Thanks for suggestions guys.

I did check the inner sill drains today, and found that they were blocked (and also a little rusty), so have unblocked them, but inside of inner & outer sills seemed to be dry - although my endoscope is not the easiest to manuever!!

Out of interest, where does water run into the sills from?

It's not the end of the world, it was more of a problem when we'd had a lot of rain or I had washed the car, after thinking the leak problem was sorted, but since I have had the passenger seat and rear carpet out, and small amount of water gets mopped up quickly - just with the crappy weather and work commitments I haven't been able to spend as much time as I'd like hunting for the leak.

I have not removed the front carpet yet as the floor does seem dry at the front, but this saturday looks fairly clear (although my head may not be after Friday night!) so will hopefully be able to spend a full day on it.

I'm going to start from scratch again to be sure it is from the bulkhead area I think, even though I am 95% sure. I will also remove the wing splash guard as Rhett suggests, to see what is going on under there. Bulkhead drains both run clear to the floor, but they could be tracking across to inner wing somewhere.

There's not much under the wing liner. From what i can understand Water in the sills should be water from out side. Think its condensation from the air con as its vented though the body and doors and the vents around the hatch frame.

http://www.porscheclubgbforum.com/tm.as ... er&#793224

did you read this......any help

Well I have the same on mine! Its not much water and I rolled a newspaper up and shoved it under the carpet twice and every time we have a torrent I will do it again.

The obvious thing is to totally seal the sunroof and see if the water stops, by sealing and spraying ultimately the leak must reveal its self.

Good luck

Very informative thread there! I wondered about the removal of the wheel arch liner, especially to have a look at the seam seals, etc. Looks like this thread covers that very well. I do recall when I repaired my S I found an area of rust under the rubber. It only came to light because I removed the wing and some of the rubber that had lifted came off too. It hadn't rusted through, so I just dealt with it and sealed it up again. However, it would have just sat there and deteriorated further if I hadn't seen it...makes me wonder about the other side now?

I had not seen that thread but removing the wing was my next port of call.

The picture above from the guy that had same problem on another forum, he also found that water was bridging across from the drain to wing/chassis seam, but he thought it was only seeping through where the side carpet was.

I actually wonder if he had sealed it up he would have found that it was causing the leak into the seat runner box section, and sealing it would have sorted that.

Tomorrow I'm going to leave a trickle of water running straight into the channel (avoiding rest of the bulkhead), to see if starts to get into the footwell. If it doesn't then I won't bother removing the wing just yet.

I had the same leak on my 1986 model and it took me ages to trace.
I ended up finding 2 leaks in all.

1. Lift the bonnet up and block off both sunroof drain pipes up, remove sunroof and pour water into the drain tubes until they fill up to the top....If the tubes don't fill up then they are either cracked on the plastic (like mine was) or have become disconnected, resulting in water coming into the cabin.

2.I sprayed waxoil intop the inner sills pretty heavily and also with the carpet removed I sealed the box section joints with sealant.
I have had no water leaks since and this is over 2 years ago. Make sure you unblock the sill drain holes afterwards.

OK, I'm now fairly confident (I've said that before!) that I've now found the leak.

I ran a hose pipe down the passenger side bulkhead drain yesterday - left it for a while, after about 10 minutes or so, the water started coming in - so that eliminated the bulkhead.

I removed the wheel arch liner in readiness for removing the wing, but found that in general it all looked pretty tidy behind there - no obvious corrosion - but as I looked closer, at the very bottom of the inner wing to chassis join, the seam sealer had broken away and you could see a gap with bare metal exposed. Pretty confident this was the leak path, I sprayed water into the joint and again, water slowly emerged from the seat runners.

I'm stuck at work so have no pictures to hand, but so far I have rust treated the bare metal (it looked pretty clean, but wanted to be sure) and have etch & zinc primed ready for sealant.

First thoughts were to seal it up with Tiger Seal, but as the factory finish along the seam is brushable sealer, I will use the same to try and keep it as original.

For now I want to get the car water tight, but come the better weather I will remove both front wings and have a proper look at both sides, and if necessary remove the old sealant and reapply, then repaint the inners. Some pictures I've seen have shown a reasonable amount of corrosion once the wings have been removed, mine looked pretty clean, but you can't be sure without removing some of the sealant.

A bit of detective work is sometimes required....

Let's hope you have solved this particular case!

So, to follow this up for anyone who may have similar problems, here is what I found.

As mentioned above, the water was pooling in the rear passenger footwell, no signs of damp from the front of the car, just appearing from the gaps beneath the seat runner mounting points.

In the end I had traced the water leak to the passenger side bulkhead drain by running a hose straight into the drain, so no water in the bulkhead area - just straight down the drain. After some minutes, the water started appearing inside the car.

After removing the arch liner this is what you have, the bulkhead drain exit is just out of shot here, but it's further up on the inner wing, and the water ends up running down the corner between the inner wing & the A pillar panel (if that's the correct terminology - the panel where the door hinge is mounted and the outer wing return bolts to):


IMG_1871 by Hallsy01, on Flickr

There is seam sealer between these two panels where they are joined, and also brushed along the seam between the a-pillar panel and the outer wing panel return. If you look a bit closer at the bottom you can see that the seam sealer has broken up:


IMG_1870 by Hallsy01, on Flickr

And there was bare metal exposed:


IMG_1873 by Hallsy01, on Flickr

So I dried this area out, treated it with some rust killer, then etch & zinc primed, before brushing this area over with seam sealer:


IMG_1874 by Hallsy01, on Flickr

Unfortunately a quick water test afterwards and I still had water getting in. Giving the whole the inner wing area a good cleanup and looking again, I could see that the seam sealer running down the inner wing had a number of cracks in it. I brushed seam sealer over this complete seam to cover any minor cracks and am now pleased to say I seem to be leak free from that area!

I left a hose running it that area for 30 mins or so, and the rear footwell stayed dry.

I still have some minor leaks around the car that I'm in the process of sorting (hatch latch seals and hatch seal), but this was the main one. With all of the heavy rain we'd been having, or a cleaning session, it would have the rear footwell soaked through.

This 944 will be watertight by the time I have finished with it!!