Plenum Chamber Drain Grommets - Every A4 B6 owner is affected by this common fault

pj123

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Just writing this as I remain suprised that there is not an obvious sticky thread for this design fault and I continue to read posts about people having problems when it rains.

Surely every A4 B6 owner has now removed the grommets in the bottom of the plenum chamber?
There are rubber grommets below battery on the left and below the brake servo on the right fill with crap and dont let water escape from the car.

If you haven't removed these it is purely a matter of time before your car fails in an expensive (water in ECU, HVAC, engine) or dangerous (brake servo failure) way.

I dont think this common fault is highlighted enough in this forum as the consequences of not sorting can cost many thousands.

How to fix the problem here
(for a passat but identical problem)
or

### UPDATED LINK Interior leaking | veedoubleu dot com ###

Take your car to a dealer and they will fix it for free.

Really hope this saves a few people from disaster.

Paul
 
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You're right in that it is a fairly common problem, but I think the worst most people see is a wet carpet, with the expensive brake servo and ecu problems being thankfully rare.

I'd second the advice in the article though and remove. clean and replace the drains rather than leave them out.
 
will audi really fix it for free and if so what do you ask them to do
 
Ask Audi if your car has had the 'Plenum Chamber Recall'. Audi used to remove the grommets and not necessarily tell the owner, now I think it is an official recall. Give them a call.

Only other tips if you do it yourself are the consequences of removing the battery. Make sure you have your radio code. Also if your key doesn't lock/unlock the car afterwards, put it into the ignition, turn to position 2, and press lock and unlock together.
 
The internal memory in the radio should hold the code for a couple of hours.

Also the ESP light might come for the first quarter of a mile or so afterwards until the sensors adjust themselves.
 
iv cleaned my ones out, i do it every autumn, a good black on an air line from under the car is normally the easy way to do it, i did think about just pulling them out, but thinking about it i decided not to as to stop dirt etc etc going up there and clogging it that way,
 
This effects loads of models not just A4s and not just B6s its very common but easily fixed
you dont even need too take the battery out you can get your hand under the panel from the engine bay and pull it out from there , sometimes removing the exspansion tank and moving it too one side helps this gives your arm more room too .
 
i wouldnt remove them completely, but i trimmed a bit off the bottom of mine so its open all the time.

Hopefully that will stop the silt building up in the holes. Its always worth checking them every 6 months to be sure though.
 
so just called audi they run a check on my car and said mine was not one of the ones with this problem and it was only certon chassisy numbered cars that had it and mine was not one of them and in the last 6 mths audi have started to send out letters to ppl who have the cars that need a re call
 
What year is your car Simon? I'm assuming the problem was mostly on the earlier b6's? I was at my local audi this morning and I would of asked them about mine if I had read this post before hand. :(
 
well mines a 52 plate mate and i asked if it was just the ones befor mine they said no it was certain chassisy numbered cars if that makes sence.
 
To be sure I would assume it is every B6 and get yours checked one way or another.

Whether you remove or regularly clean is your call. All the silt and dirt that washes down your windscreen goes through the plenum chamber so I am not worried about two holes allowing a small amount of dirt upwards through the holes so I chose to remove the grommets and this is the Audi 'fix'. My S3 just has two holes to the outside world at either end of the chamber.

I'm glad this thread is helping create awareness of the problem. I wish I had known about it before owning the car for a year. One of mine below the servo was totally blocked.

Paul
 
yeah i will keep an eye on mine just to be safe iv had the car just over a year now and have never seen any warter in there at all always seems very dry. but like i say it will not kill me or any one to have a look every time you wash the car to be safe. thanks paul
 
Ive seen water in 03 plate cars so just pull the bungs its done and no need to worry then :)
 
did mine yesterday while i had the battery out! easy enough and there was plenty of crap in the grommets!! mines also a 52 plate simon and ive seen water in there before hence taking them out!!
 
well i can only go buy what audi have told me and that was certain chassisy numbered cars not reg/year mate i dont now how they can say this mind but they are 100% sure there where some chassisy numbers that have this problem and some that dont go figer a i will still keep an eye on mine like i said and the first time i see it i will take it to them to fix. but as of yet its always been dry. luckly
 
Mine was a 52 plate. The older the car the more dirt they will have collected!

I think Audi will only recall ones below a certain age and that is why your chassis was not listed.
 
i can only go buy what i was told mate some chassis had this problem and otheres did not
 
i can only go buy what i was told mate some chassis had this problem and otheres did not

With respect I disagree, you can get under the bonnet yourself and have a look or you can take the car to the garage and ask them to look at it for you.

Given the consequences I dont see why you would assume everything is ok. Ignore Audi, they are wrong.
 
i can only go buy what i was told mate some chassis had this problem and otheres did not

Hi guys,

I too phoned audi (east kent) today & they told me its only certain chassis numbers that this affects but i gave them mine and my fathers but they said they were not included, so thats 3 different cars all different years, so which ones are getting the recall, seems a bit like they dont want to do them to me:banghead:
 
well i can only go buy what audi have told me and that was certain chassisy numbered cars not reg/year mate i dont now how they can say this mind but they are 100% sure there where some chassisy numbers that have this problem and some that dont go figer a i will still keep an eye on mine like i said and the first time i see it i will take it to them to fix. but as of yet its always been dry. luckly
Mine was dry on a 51 plate but having seen so many i pulled them just to be sure its not worth the risk and i dont see your issue "just do it "
 
With respect I disagree, you can get under the bonnet yourself and have a look or you can take the car to the garage and ask them to look at it for you.

Given the consequences I dont see why you would assume everything is ok. Ignore Audi, they are wrong.

i do keep an eye on mine and its always been dry if i see it filling up it will be the first thing i do but in the year or so iv had my car its been ok so fingers crosed it will stay that way
 
Mine was dry on a 51 plate but having seen so many i pulled them just to be sure its not worth the risk and i dont see your issue "just do it "

are they easy to get at mate and just pull them out also what are they there for if they just make problems
 
they are rubber gromets with holes in them to let the water out but they can block up. i have mine out.
 
thanks for the where they are bass666 i new what they would look like thought :) just was not sure where and best way to get at them
 
I called Audi and they said mine was due a recall so in it went. They took 45 mins to do it and when they came to give me the car back they had done a full vehicle inspection. 5 mins to remove the bungs and 40 mins looking for work! They certainly never removed the battery so all i can presume is that they removed the bungs all together. I only called them because there was around 1 inch of water sat in there no damage though. My car is a 2001 and was registered 10/01.
 
If you have a car lift then you can reach up and pull them out or clean them out from below. If you dont have this kind of access then follow the how to guide at the top of this thread.
 
:banghead:
I had already told you how to remove them from under the bonnet.

yes you did but you did not say where they where you said just get your hand under the panel from the engine bay and pull it out from there so me being well me asked where they where so i dont have to take the hole lot out if i did not need to ;-)
 
Had this problem on a B5 some years ago and worked out that you can feel for the holes with a long bottle brush and push through the blockages then clean out with a hose until the water runs clear out of the drains.I dont think the bungs came out but I regularly checked the chamber for the next 5 years and vacuumed any litter out and no more problems.So far the replacement B6 has not been any bother but I still keep it cleaned out because I have to park under trees overhanging the drive,Obviously Audi Bung Design Dept needs to learn from others if they have not revised the item yet
 
audi recalled mine and did the fix. mines a 2001.

Was the recall done recently?

Should those affected be expecting some correspondence from Audi regarding this?
 
did you actually get a letter after 9 years? Or did you ask in audi?
 
First of all a massive thanks for reminding me and other users of this known problem, i had a few spare mins this am and thought i,d check this again, and guess what ! the water level was about 3 inches in there! ....now mine did get recalled late last year it was a recall notice i posted on here 51B7 was audis recall number, they did the unblocking of the so called plenum chamber, all tickety boo... now considering ive only done approx 3 thousand miles since then, i was surprised to see how much crap/silt/dirt was in the actual rubber bungs and area around the battery and servo unit, so needless to say i have removed them all together, hopefully a final soloution to the problem. As said remove the battery it is much easier to remove the bungs with the battery out, dont worry your radio didnt need the code and yep the traction light does illuminate as already posted and like others say, i expect this to go out after a short drive.
so a massive thanks to you! saved a potential big bill!
by the way mine is a 2002
cheers!
 
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