Water in Rear Footwells

[clyde]

I was giving the rear footwells their bi-annual clean today - nobody's ever in the back so they don't really need done much; I do clean the front footwells more often honestly.

Anyway, I removed the mat and the carpet on the off-side and noticed that the underlay was a bit loose. On closer investigation it became clear that the felt was actually wet and the glue had become unstuck in a small part. I teased this off and not all but a fair amount of the felt was quite sodden. The near side one was pretty much the same.

The thing is I cannot work out where the water could possibly have got in. The floor is sound and there's no plugs or anything like that missing. The rest of the surrounding glued carpets are all dry on the surface but I'm not sure about their backs but without ripping them all out (which I don't want to do if I can help it) I cannot say for sure.

I do not have a sunroof, although I think the drain tubes for these run down the A pillers in any event if I remember correctly.

The only thing I can think of is that during the heavy rain we had in January I went through quite a few very deep puddles and it's possible that water was forced into somewhere that it doesn't normally get forced into.

Any advice or pointers would be greatly appreciated

 

[Stewart Rix]

A friend had this problem before Christmas. Foot well carpets we absolutely soaked. Turned out to be a seal on the chassis cross member was damaged - it's somehow connected to the ventilation system, Paul at Northway is your man to speak to; he found and fixed it.

 

[gxc67]

I was said friend(see Stewarts post), and I found the front felt was actually wet as well, although in my car it was only drivers side. You cant easily tell the front one is wet without getting it up, as the top surface is reasonably waterproof, and the underside is like a huge sponge.

Water came in through the cross member end at the front, and gradually drifted back. The fresh air intake at the front of the car is connected to the chassis crossmember, and the seals on the ends are at risk of damage from road debris, and given they are now 14+ years old, can give.

A new load of sealant at very little cost sorted it. You will need the floor felts out and in the airing cupboard to dry, and also so the ingress can be checked with a hose or the like. They do dry out eventually, but the front one takes a while.

 

[clyde]

I only had a quick look at the front 'wells when taking the mats and carpet out but all seemed dry. I'll have another look tomorrow just to make sure. I hope it hasn't migrated from the front to the back as there's an awful lot of electronics below the passanger seat (LHD).

Not sure I understand the water path from the cross-member to the inside of the cabin though. I can see a day of scrambling below the car trying to suss it out coming up this weekend. Northway are bit too far from me

Left the rear sound deadening propped up against the kitchen radiator and they're virtually dry now. Didn't even try putting them in the airing cupboard as the smell of damp felt isn't very nice [8|]

 

[911sse]

When this happened on my 3.2 Carrera it was the seal to the back windows which had gone, although they looked visually intact.

 

[Mark Elder]

Hi Clyde,
I've had this happen several times to me - but reading above maybe I should not have given up and should have tried to fix the cause. Definitely caused by driving through floods or large puddles. (I now go on huge detours to avoid them or know I'll be carpet drying for a week!)

I've only ever found it in rear footwells but (I my view) it gets there via water getting into cills at front (ie behind front tyre), along cill then across the cross member under seats. You can see small gaps at the edge of the floor ridges where it joins the cross member - I've seen it leaking through just after driving through a flood.

But above seem to suggest fresh air intake as initial source (which one anyone?)

Mark

 

[Porker993]

ORIGINAL: Mark Elder

You can see small gaps at the edge of the floor ridges where it joins the cross member - I've seen it leaking through just after driving through a flood.

Mark

That is good research, and fits with my experience.

Rear window seals are the other option - as 911sse says above. As with me, both went at once, so although fixing the rear window seals helped, it did not fully cure the problem, as everytime I drove through three or four inches of water, the problem re-appeared.

 

[Mark Elder]

ORIGINAL: gxc67
....The fresh air intake at the front of the car is connected to the chassis crossmember, and the seals on the ends are at risk of damage from road debris, ....

So where exactly are these vents and seals?

A picture would be good.

Sounds like an easy job to fix what is a real pain in the west of Scotland! It's raining today...

 

[993 C4]

Could be worth checking both of the white plastic door membranes. May sound daft but even a slight tear in the wrong place could eventually result in soaking wet foam under carpet footwell panels.....Water can travel anywhere and usually starts from where you least expect it.....

 

[clyde]

I've had a look tonight and the front sound deadening is drier than a dry thing sitting in the middle of the Gobi dessert at high noon. So I'm pretty certain that the water isn't getting in from the front and working its way back, thank goodness. But I will have a look at this area next time its on a ramp.

I take it you mean the rear side windows 911sse? I can see that it's not the rear window but it's not impossible that some water could be getting past the seals in the side windows. I don't think so as the carpet going up the sides of the footwell and seat base do not seem wet and they would need to have been soaking to transmit as much water as was in the sound deadening.

I like Mark's proposition better (not least because it seems easier to fix []) so I'll have a look in daylight at the next opportunity. If it's the cross-member/floor pan joint presumably a bit of mastic squirted in will do the job?

I'll let you know how I get on.

 

[clyde]

ORIGINAL: 993 C4

Could be worth checking both of the white plastic door membranes. May sound daft but even a slight tear in the wrong place could eventually result in soaking wet foam under carpet footwell panels.....Water can travel anywhere and usually starts from where you least expect it.....

Got interupted before I sent my earlier post, so overlapped with this one.

I know what you mean but I think I have far too much water for it to be getting past the door membranes - I could have wrung the deadening out like sponges were it not for the bitumen-like finish on the top sides. As it was I put an old towel either side and stood on them and ended up with two very sodden towels.

 

[IndischRot]

ORIGINAL: 993 C4

Could be worth checking both of the white plastic door membranes. May sound daft but even a slight tear in the wrong place could eventually result in soaking wet foam under carpet footwell panels.....Water can travel anywhere and usually starts from where you least expect it.....

This is where I would put my money... the membrane acts like a shower curtain and keeps any rain that gets past the felt window seal from getting to the door card. With age the glue fails. Carefully heck the bottom edges of the door cards for any signs of water stains. Also check the drain holes in the base of the door to ensure they're clear.

 

[clyde]

ORIGINAL: phelix

ORIGINAL: 993 C4

Could be worth checking both of the white plastic door membranes. May sound daft but even a slight tear in the wrong place could eventually result in soaking wet foam under carpet footwell panels.....Water can travel anywhere and usually starts from where you least expect it.....

This is where I would put my money... the membrane acts like a shower curtain and keeps any rain that gets past the felt window seal from getting to the door card. With age the glue fails. Carefully heck the bottom edges of the door cards for any signs of water stains. Also check the drain holes in the base of the door to ensure they're clear.

Definitely not phelix. I think Mark was bang on the money with the water getting in to the rear footwells from the seam in the floor, there's what looks like a gap were it meets the cross member. It could probably be sealed from the inside with mastic but I think I would rather do it from the underside as I suspect that's where it was originally sealed. Assuming of course that it's possible to get at the seam, which it probably isn't.

 

[gaity]

I had exactly the same problem which turned out to be poor sealing/corrosion around the bottom corners of the rear screen, under the rubber seal. I understand the screen has an alloy channel around it that corrodes. Water pools in the lower corners and just dribbles in, down the sides of the rear shelf and finds its way into the rear footwells via the rear seat wells. Check under the carpet in the seat wells - if it's wet up there my money would be on rear screen. I attempted to cure this by having the rear screen removed and rebonded but it didn't work as the alloy channel couldn't be replaced (part of screen assembly). Brand new screen cured it - thank you RAC insurance!

BTW - it's difficult to tell what other parts are wet without pulling up at least some of the carpet and felt, as the sound deadening felt has a heavy waterproof coating that will keep the carpet on top dry. You couldn't tell from the top that there was a litre of water sitting under the carpet in the seat wells!

 

[Porker993]

^ +1

There are multiple possible sources for water in a 911/993.

 

[clyde]

My main reason for believing that it's the floor seal at the front of the footwells is that all the carpets surrounding the rear footwells (that is up the inner cill, up the rear of the footwells and up the central tunnel) were all bone dry. I pealed them all back a bit to make sure and there was no evidence of the slightest bit of moisture below.

I did notice at the week-end that I've managed to loose the section of undertray that sits in front of the engine undertray somehow, so that maybe has something to do with it. So I'll need to get a new one of them but before I fit it I'll have a proper look around underneath.