Plenum drains blocked - a helpfull guide.

[Jimmo]

I'd just like to say cheers for all the helpful info above. I found my rear passenger footwell absolutely sodding with water this week and thought I'd read something on here before about a common problem, so I did a search.

My rear footwell has been slightly wet before but i though it may have been from peoples feet etc getting into the car after walking in the rain. Only had the car a year now but suspect this problem existed before my ownership as I inherited a few intermittent electrical gremlins (possible related to the module). Wasn't that bothered as the price of the car was a steal and the gremlins are tolerable.

Followed the guide on here, poked my finger through the hole and swooosh. I'll be keeping my eye on it from now on

Does anyone have any thoughts on this problem potentially affecting the car later in its life with corrosion/rusting of the floor pan?

Thanks folks, one of the great things about these forums is the wealth of info.

[madrob6]

Regarding the rust under the carpets. Mine had a slight bit of surface rust from where the water had been sat there for so long so I stripped out the entire carpet, sanded it back down to bare metal and painted it up again with some anti-rust primer to stop it coming back.

[WESTY73]

Well well, turns out it's not just blocked plenum drains that can cover your CCM in water.
For the past few months I've been having electrical problems that have been getting worse & worse despite clearing out the drain holes. This week things came to a head when the alarm started sounding constantly & I lost all interior lights & remote central locking, I thought 'this is just getting silly'
A mechanic freind said there may be a hose for the rear washers running along one side of passenger footwell (?) that's leaking, so I ran with the tank empty for a few days despite risking a fine by the old bill, but that didn't help so after every drive I siphoned out the water & as it's been dry today I went for a long drive so I could tell for definate if it was rain water & as a puddle formed despite no rain then I deduced that it must be.......the heater matrix!!! this was confirmed as I siphoned todays water out into a milk bottle & it had a dirty pink tinge to it (this source wasn't obvious to start with as I have a slight coolant leak elsewhere (just a slow drip) & have to top up the bottle about once a week anyway).
So, how much of a pain in the rear are heater matrices? could a (very) amatuer mechanic attempt one or should I just start saving the pennies to pay my local VW specialist (or even any old garage)? As it is I have to save up for either a CCM (tho gotta love having a mate at VWparts) or the wiring loom to one. I've dried out the CCM & wiring by running it on top of the footwell carpet & got most functions back tho inside CCM box seemed bone dry so could just be rotten wires? & yes I will take out complete carpet to dry properly when matrix is done
Hope this helps others with wet footwells, the lesson is if you have to remove any water do so into a clear container to see if it's pink!

[Ste_Nova]

heater matrix.... that will be a dash out job then

[the_dubmeister]

Just been out to my car about 30 mins ago to pop the disklok on the car reaches behind the drivers seat to pick it up and the rear floor behind drivers seat is absoloutly drenched in water, just spent 10 mins now draining half of it out even at this time in the morning lol.

Opened my bonnet up and there we are a river where the battery and master cylinder is, looks like thats a job for tommorow morning then

[NickBab]

Been suffering with a damp passenger side rear carpet for months and have been dreading taking this to VW to get fixed. My local garage didn't have a clue so this was my next action until I found this forum. Just unplugged these drainage holes and now have my fingers crossed this has fixed the problem - thanks for the advise.

Did anyone else have problems getting the battery out? My battery is much larger than the one in the pictures and was a complete pig to get in and out.

Also, anyone got any ideas how to get rid of the smell from months of damp carpets?

The carpet is dry at the moment, fingers crossed it stays that way.

[madrob6]

My carpets didn't really smell but I took them out and left them on the roof of the car for a week or so (easy enough when you don't have to use it) as the sound proofing is so thick that it takes a while to dry out properly even if it feels dry.

I guess the only real way to get rid of theh smell is to get them professionally cleaned by no idea how much that would cost or whether it would work with them inside the car.

[WESTY73]

Hey NickBab
I'd suggest doing the same as madrob6 & take out the carpets to dry for quite a while, mine's coming out this weekend & I'm putting the seats etc back in & running the car without carpets for a month or so despie noise/heat issues. Just thought it would be better to leave it out until I've identified & cured any entry points for water (I have at least two!) without having to keep on drying the car out. Then I just have to fit a new CCM (or CCCU as VW trade parts centre seems to call it?) & wiring.
Regarding the battery removal, I found it a lot easier if you remove the cabin filter cover first, held on by 1 cross-head screw if it's like my 1.8T B5. If you don't know it it's the black plastic vagueley triangular thingy that sticks out from below the windscreen just between the battery & the nearside bonnet hinge, tho this can be a bit fiddly to remove/replace until you get the hang of it

[NickBab]

Thanks for the advise, the carpets are dry at the moment so I think I'll leave it for a week or two to see if the smell goes.

It's amazing this is such a common problem. My drains were completely blocked, this must be the same for hundreds (or more) passat owners.

[Gary]

It's amazing this is such a common problem. My drains were completely blocked, this must be the same for hundreds (or more) passat owners.

Nick, it's a VW recall on affected cars - they just don't want too many people to know! :

viewtopic.php?f=8&t=6992

Gaz

[scouse phil]

very helpfull this had ago the other day wasnt to bad but took me 15mins to get me hand back out, i was shocked by the amount of crap that had collected

[Jk*]

I have just been out to mine to have a look at mine. Pulled up the passenger side carpet (front) where the Central locking unit is to find...About an inch of water down there. Please note i did empty my Plenum drains about 3 weeks ago but didnt think to check under the carpet!

IF YOU CLEANING YOUR PLENUM DRAINS CHECK UNDER THE PASSENGER FRONT CARPET TOO as there is a chance you will have some water there.

After opening up the casing for the central locking unit it appeared that it had escaped the water however the water had obviosuly gone all over the wires! I used a chamois to get the water out which worked VERY well. I am currently holding the carpet up to dry off as well as the wires. The pictures below show what ive done. Hope it helps.

N.B- I did NOT remove the front seat as i didnt have a torx end.

[vygec]

Ive just become a victim , for a couple of months i noticed dirty sock smell in the car, so invested in some decent air freshners , however, after reading this i checked the drivers footwell underneath the mat, and it was completely wet!!
So will be attacking the drainholes this weekend, however, i had a good check, and the passenger side footwell is totally dry, every post so far i have read with this problem points to the passenger side getting wet, but with me its the opposite.
is it still the drain holes causing the problem for me?

another note, i now know why my alarm comes on completely randomly and the fact that there is a constant smell of old socks in the car.
!
Ta.

[madrob6]

Mine was flooding the drivers side for a couple of reasons.

Firstly the grommet for the bonet release cable had split so got a new one from the dealers.

Secondly the seal for the inner door skin had perished on the front and rear doors. Replaced with dum dum tape and the car is now water tight again.

I did have to completely remove the carpet in order for it to dry out fully though.

[bakili]

Has anyone tried to use drain unblocking chemicals?
I know sounds little bit stupid, just really don't want remove battery.
I have no sign yet, but reading this post makes me so worried.
I tried to get my hand under battery, and it looks dry under.

[Jk*]

Just keep an eye on it then after a rainy day.

[bakili]

I mean if anyone tried to use bleach or other drain unblocking staff, without taking battery out.
What you think guys?

[Jk*]

It might work. However if it is blocked and doesnt clear it you are going to end up with a lot of bleach in your car and you having to put your hand in it to clear it.

I would just keep an eye on it, or hope for a dry day and get out there and do it. Takes about 30 mins with the right tools.

[bakili]

Thanks for advice guys,
So it was nice weather today after rainy night. So i took battery cover out just to see if any water under battery. It was just bit damp, anyway decided to take battery out, good i checked before, turns out that i don't have radio code . I left taking battery out, just gave good clean around bonnet hinges, they were bit dirty but anyway good clean with tooth brush. It was no sign of water in pollen filter box, or around it. Right hand side was bit pain in ****
anyway freed all channels. After i parked car on dry spot and run about 1,5 liters of hot water, looked under car, and it was water under car.
So guys does it mean plenum drains are not blocked yet?

[Jk*]

Seems as though they might be free from blockages!

[bakili]

Thanks JK
I will get it checked anyway, in soon future

[marydoll]

if you have owners manual the radio code is in there hope u have it


paul

[bakili]

no i checked, its not there.
Have to go to dealer to get one, i hope itt will be free

[marydoll]

yes i am having the same problems windows door locks and sunroof checked all the fuses fine took nout relays today and will be replacing them tomorow as a matter of course.

ccm bone dry drivers door still locks of the key that the only one have a faulty door module on passaenger side would that affect all the electrics

if u quote your chassis number think the dealers will give the radio code tto you

when i fit new relays and problem still there then its time to get it vag commed

paul

[bakili]

$tealer tried to charge me today £20 for radio code, after i told them it should be obtained for free (stated in owners manual) they told that i can get it for free but only from where car originally was purchased. I phoned VW dealer where car was first registered, but they said that they cant give over phone, i need to prove that car belongs to me. So 15miles trip for me tomorrow to Rotherham.