Still water in rear passenger footwell
 

So I have had an issue in the rear passenger footwell with lots of water building up (thank god there is no ECUs located there).

On the weekend I cleaned out the HVAC drains either side of the center console with compressed air, removed the passenger seat to gain access, hoovered under the rear carpet for about an hour and then dried the foam and carpet with a heat gun. So it was almost bone dry.

Today after checking again its once more satiated with water.
There is no water either side in the front so i don't think the orange HVAC tubes are leaking and there is no water behind the driver seat.

I have followed this guide http://www.audipages.com/Tech_Articl...tordrains.html
but is there any more info or does anyone know what else could be leaking water in to the rear footwell? Someone said the HVAC drains are usually the issue but I dont see how water could be coming so far to the rear with out any of the other areas getting wet...

Many thanks in advance.
Bo

Re Wet
 

I'm having the same issue, had it for a while..... and cannot seem to find a source of the problem....

Mines the same everything seems to drain ok.... but if heavy downpour.... (well not always so heavy) I notice the carpet is wet front to back (but seems to sit to the rear)..

Doing my head in..... I'm starting to think I'll need to remove the dash and see if it's leaking from the windowscreen or something..


I will keep messing.... and will keep an eye on this in case you come up with something :-)

Good Luck

In my experience, lots of water in the rear footwells is usually caused by a blocked centre cowl drain (engine bay, under the air intake box). Shine a torch down there and check if you have any standing water.

Centre drains for sure for wet passenger floor. Best to go in from the drivers side.

Hole at back
 

Well having looked at other posts....


I have indeed found a hole at the back under the air con pipes where they bend left (next to the electronics box in the right hand side of the engine bay).

Looked good ... welll was a faint line.... kinda just looked like how the sealing compond they used was..... however gently push that area and it just started to fall away and reveal the hole...

Cleaned it the best I can.....and put some sealant in and around the hole....

Not ideal weather so bloody cold.... but I did leave the engine running..... to get the car warm and engine bay so hopefully it will bond seal

Car is still not dry yet..... so I guess will see if it continues to dry out... or when the rain comes gets wetter... of course... it could still be getting in else where but was deffo getting in here... so at least one stop plugged :-)

Pic
 

Attachment 15157

Hole where the white patch is

Not quite sure, but is that the infamous Botang's hole?

Looks like it to me.

I don't think there would be sufficient water getting through Botang's to soak the rear footwells ... would there?

I'd have expected damp front footwells at the most.

That's what I thought.
The hole you have there is indeed botangs and will benefit from sealing it up anyway.
You can hear water sloshing if the centre drains are blocked as you corner.

hole
 

Well centre drains are clear and I get no sounds of any sloshing of water.... both holes are clear left and right over wings.... and the I only ever seem to get water in mine... on the passenger side.

Well I've sealed this hole that clearly needed doing and will report back, once it's either dried out or carried on getting wet.


I would have got rid of the car by now... but as I've had it for 14 years.... and have to say it been my only real on-going niggle.....

Had this problem and found that the water was coming out of the rear air vents under acceleration. Turns out the whole vent system was full of water.
Drilled a small hole in pipework to drain all the water out.

I just laid towels over the seats behind the rear vents to catch the spray and directed all the airflow through them at max fan speed and max temperature. Cleared in a reasonable time, after a lot of gurgling and spraying.

To clear the vents of water, or rather the centre tunnel that feeds air to them, the best/quickest way I found was to use J-cloths:

Remove the rear vent first (couple of screws and plugs, takes just seconds). Then, using a continuous roll of J-cloths like this tear off a length about 2-3ft long. Twist it tightly and keep turning it as you poke it down the vent. Repeat a few times until the J-cloths come out dry.

Use duck tape to attach small hose to vet&dry vacuum cleaner and suck it out.

No more water
 

Well since sealing that hole...... and front is now totally dry, rear was still wet but having lifted the back seat to pull carpet up... and switching tea towels every few days... that nearly dry too..... or course had it been summer would already be dry but.... getting there....

have had rain and nothing so far......

time will tell for sure.... but deffo looking good so far.,...


Do no doubt this has been the problem with mine for many years as I can remember the pass side being wet (on and off) many years ago .... on and off..

So I'd say even if ya have a dry interior ..... then come summer time, might be worth poking around and make sure that hole is sealed well..

Daz

Finally sorted.
 

So I left the car parked up all winter under cover and since its been out the last couple of weeks with some rain there was again water in the foam of the rear footwell.

It turns out that this hole to the right side of the ECU box under the air con pipes was leaking in water. It was coming in to the passenger footwell and then traveling to the rear in a recess that I had missed before when I checked for moisture in the front.

Since I plugged the hole with a bolt and plenty of sealant its dry! +++

Thanks for all the pointers, I would never have found that with out the references.

Will get the car ready to sell it now as the D3 just arrived :cool:

That sounds like the infamous "Botang's hole"! :ROFL:

i have water under my drivers matt? any idea, the whole matt the sponge bit gets soaked through

Most likely either blocked drains under the bonnet or your aircon drains. I would check your drains under the bonnet first. Look for standing water either side, just under the window. Also the centre drain: Shine a torch down the side of the cabin ventilation intake and look for water, or get a hose and pour some water down to make sure it's draining away.

I have the same problem
 

Hello.

Same problem for me here, always dampness at the rear of the passenger footwell with no obvious source except perhaps the door seal. I put some rubber "gummipflege" on the seals allround as I can only think it's the door, weirdly the wet patch only stems from the rear centre of the foot well and there are no obvious ingress there, cowls are clear, driver side is fine.

I am veering for the door but It's not too drastic...

Since the car has been offroad for some time, it might be worth checking out the following thread on the drains:

https://forum.a8parts.co.uk/showthread.php?t=16008

As for the dampness at the rear of the passenger footwell, it might be possible that the water is getting in from the O2 sensor grommet, which is located in that area, especially as Botang's hole and A/C overflow blockage would soak the front of the passenger footwell.

My previous A8 used to get water coming through the rear passenger air vents, behind the central armrest, I believe caused by blocked drains somewhere, but never did resolve as the gearbox failed shortly after this issue and it was scrapped anyway

I believe water coming through the rear vents is caused by blocked drains from the HVAC system. It's the orange drain pipes either side of the transmission tunnel in the thread linked to above.