Check your drain holes, people

AndyMac

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Wondered why my car kept steaming up recently, even the aircon was struggling to keep the windows clear. On investigation I had about an inch of water underneath the carpets on the passenger side front & back. Spent all today bailing out the car and squeezing the foam out. Ended up with 3.5 litres of water removed from under the carpets and it was only damp in the rear passenger footwell. Couldn't believe how much water the foam absorbs before it starts to show through.
Why don't Audi put a waterproof backing on the thick foam underneath the carpets? Squeezing it out is a real pain.
Think I'm there now, had the carpets propped up with a heater blower on them all afternoon.
Cleared out about a pint of gunk from underneath the battery and round behind the ECU. It was fairly dry but the drain holes were well blocked and with the really heavy rain we've had I guess they couldn't cope. Anyway I'm hoping that was the reason. What fun on a Sunday!
 
My mate changed the battery on his Girlfriends B5 and there was literally litres of water trapped underneath it!
 
i had the same thing on the driver's side before, mechanic had been arsin about with the bonnet catch cable and had managed to pull out the rubber grommit. took like two seconds to pop it back in again, and its never happened again, but i wasn't too pleased at the time.

will check out drain holes sometime this week just out of interest.
 
It's funny that, I was just thinking to myself yesterday how badly mine is steaming up!
Under the battery is the place to start I guess? I know how to get the battery cover part off, but what about the rest of it?
 
It's all pretty obvious once you're under there, I didn't remove the ECU, just used a wire coathanger with the end bent into a loop to drag all the muck out.
DrainHolesB5.jpg
 
OK nice one.

Any proceedure to follow in regard to alarm / ignition / doors open or shut while battery is disconnected?
 
The same thing happed to me a few months ago but a bit of plastic from the trim around the wiper arms had broken off and was blocking the drain. Lucky i found it before any of the real rain came it
 
JayB5UK said:
OK nice one.

Any proceedure to follow in regard to alarm / ignition / doors open or shut while battery is disconnected?

No I just went ahead with the car unlocked, had no problems, although my A4 always runs a bit rough after the battery's been disconnected while the ECU settles down.
 
sorry to bring this up Im looking at the pic and wondering where that is on the car? and is that an a4?
 
oh right i have the non quattro so i assume its in the same place and if i remove the battery will everything reset???
 
Yes exactly the same on non-quattros. You only need to ensure you have the HU security code as this will go into SAFE mode. The engine may run a little rough for the first few miles as well as the ECU figures everything out.
 
AndyMac said:
Yes exactly the same on non-quattros. You only need to ensure you have the HU security code as this will go into SAFE mode. The engine may run a little rough for the first few miles as well as the ECU figures everything out.

ahhh that could be a problem where in god name would i find that! where do you put that in?
 
It should be on a tear out card on the inside of the owners manual for the stereo.
It's a 4 digit code that you enter on the HU itself. Instructions are in the manual as well, they differ slightly depending whether you have a Concert/Delta/Chorus/Symphony.
If in doubt, then I'd use a portable jump starter or even a battery charger clipped onto the leads before you remove the battery to keep the 12v's going while you remove the battery.
 
Cleared those drain holes out about two months ago under the battery tray and the servo so there's no water collecting in that area but the carpet is
still soaking wet behind the passenger's seat.
I've got a few days off this week so I'll try and get the carpet up.
Anyone discovered where else it could be coming from?
 
I presume you completely dried the carpet out the first time round?
As I said I bailed out 4 litres of water from mine and it wasn't even showing through the carpets. There is so much unprotected foam underneath it's quite a task to squeeze it all out, then prop up all the carpet front & back and leave a blow heater going at it for a few hours until the windows stop steaming up. Took me the best part of a day. There's no way it would dry out by itself.
 
there's also a tray/collector above the pollen filter, when i checked mine the drain on that was blocked which was allowing water to gather then overflow down into the filter and into the heater plenum chamber.
 
a mate had a £1200 bill on an A4 (a 2001 tdi SE) a couple of years back, replacing the whole electrics module under the bonnet (drivers side at the rear I think) as it was completely corroded out where water had collected there - first he knew was when it completely failed, would not start at all, RAC had to tow him to the dealer.. out of warranty which was a ******..
 
Yes remember to clean out the impossible to get to bits under the wiper splash guard (above the ECU) where all the leaves collect.
 
Hey Andy,

I never knew it was a national holiday down where you are..... I mean to find time to help others on the board... Jeeeeeezzzz

Make sure you use that "National Holiday" well amigo ....it will be a while before another comes along in that World of your own!:haha: :rock:
 
I cleared the drain hole by removing battery and cleaing and water now flows free out the drian
Water seems to collect under the servo.
Can you please confirm that there is a another drain hole under the servo and its location, i cannot see it?.
 
is it ok to disconnect the batery? what will happen if i return it back...i dont know any code from my car.
 
I just had to bail out the A6 like some kind of cheap boat!
parked on a slope the rear driver side footwell had 3" of water in it!

I have even drilled 2 x 1/2" holes inside the scuttle tray!
stupid stupid design
 
aarrghh! there's TWO drain holes? I dragged out the battery on Sunday because of the tell tale misty up windows. While taking off the awkward bracket that locks the battery in I noticed that the bracket holdy bolt looked newer that the other bolts. Sure enough the drain hole was blocked by..... ... the origional bolt.

Funnily enough when I reconnected the battery my 2.5 tdi auto seemed to pick up quicker - my Boy's volvo used to have a snow mode on the auto box which held the revs and slipped the clutch to avoid wheelspin in the snow and before it felt like that. After reconection much quicker pick up. Also (I know there is no logic to this at all)before the temperature clock was all over the place even with a new CTS after the reboot the guage went up to 90 and stayed there. I know, weird? I could love this crazy car anymore. Sad eh?
 
Funny both my A4 A6 were both were full of water although too late for the A6 overflowed into passenger footwell.
My A4 was more lucky.
Took both batterys and trays out and cleared holes water poured out.
Dosn't take much to clogg them, besides a lot of heavy rain in sunny cardiff lately.
 
Both my B5 A4 and my fathers A6 had this problem on my fathers car it was much worse as you could see the water actually coming through.
I think we were both lucky as both our cars are poverty spec so we don't have all the electric gubbins to go wrong.
On both cars I have thrown the bungs away and have never had any bad effects at least you know that way it will never get blocked again.
I notice under the bonnet on the later b5 A4s there has been a redesign as it has a mesh grill over the scuttle area to stop leaves from entering but even then I wouldn't trust it.
I would just remove the drain bungs and be done with it that way you know you are safe, I think the bungs are only there due to audi over engineering things.
 
Had same problem, the water was about 2mm of top of ecu , took battery out and rubber gromit was solid with probably 12 years of crud, finally got carpets dry , think its coming in by rear view mirror now , worth checking cause 5 mins taking battery out can save days of drying carpets and nearly wrecked ecu s...
 
Thanks to this thread I checked mine and I'm glad I did as it was full of crud. Well worth the half hour it took :)
 
Yep same instant result ... no more misty up windows. Also gave scuttle a good clean out generally and replaced the cabin filter. Nice warm glow from caring for aged Audi....
 
My carpets are soaking wet, driver's side front and rear.
I took the scuttle panel off but now I'm out of my depth.
Any pics so I can see what I'm doing?
And can't even consider taking carpet up, will they dry with the heater?

Sent from my H3113 using Tapatalk
 

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