Scuttle / Plenum drainage issues

[ESD1711]

Ok, so whilst fitting the scuttle covered in this thread:


http://www.audi-sport.net/vb/audi-s...scuttle-cover-wheres-best-place-get-them.html


I've come across a potentially serious issue with the A4. It's been covered before, but its not one I'd have known a thing about without looking for - I'd urge you all to go check this on your own car.


Basically, the drainage plugs in the scuttle get blocked up and rather than pour back out through the bottom, any rain water or whatever else that runs down your window gathers in your scuttle, effectively turning it in to a bath.


This can lead to serious issues with leaking interiors and, worse still, faults with your CCM.


Thankfully I've had no issues and it doesn't appear like I've any leaks anywhere, but when checking, mine was holding a LOT of water.


The fix I was told when visiting audi is just to remove the rubber grommet from under your battery, which I've now done.


However - I'm not convinced the grommet I've removed is the correct one, as I did so just with everything in place and reaching under the battery. Are there any other grommets around there which should stay in place?! The one I've removed is pretty large and doesn't have any holes in it?!


Its probably better to remove your battery and get a better look, but its chucking it down here just now so I just did this quickly with everything in place.


I'd recommend you all go look in your scuttle though to make sure.

 

[mearnsA4]

Mine was full of water and I did the exact same as you removing the grommet under the battery and the water drained away. I think there is another one on the opposite side under the break servo..

 

[ESD1711]

Yeah, I'm 99% sure I removed the wrong one. But I'm gonna whap the battery out and get a better look today.


This is the one I removed.... It did the job or draining the scuttle, but defo not the 'correct' one

 

[mearnsA4]

I think that is the same one as I removed, looking at it seems the right dimensions, but tbh i didn't even see it as I pushed it inwards and left it there.. I guess if the water drains then that is problem solved..... What is that dot in the middle.?

 

[mearnsA4]

Good luck with removing the battery by the way.... I tried but gave up as it didn't seem to want to move....

 

[ESD1711]

As suspected, the one I removed above was the wrong one..... Although I'd imagine it would do the job anyway!


Got the battery out and got rid of the two proper drainage plugs today. The one under the servo wasn't too bad, but the one under the battery was properly clogged up.


Problem solved now though

 

[mearnsA4]

Good stuff, glad you got it solved... I basically was feeling around under the battery and popped a grommet which let the water drain so never saw the layout but was well glad to get rid of the water.

 

[ESD1711]

Yeah thats basically what i'd done originally and removed the grommet pictured. In fairness, it does the job.

The actual drainage ones are a bit deeper in though - think it'd be hard to reach that far back from just feeling about. It becomes a lot more apparent when the battery comes out.

Just really surprised that there's not more said about this - i've been floating about the forum for a few months and hadnt seen it mentioned before...... massive design flaw that effects a whole host of different models.

 

[wangdoodle]

I had this when I went to view my A4 & bought it to the attention of the dealer,so think I'll re visit it!

One of mechanics came out with a piece of wire & prodded about until it drained.
I couldn't believe how much was in there,about a quarter of the way up the battery....could have put gold fish in there!!!

 

[A4_MaJiK]

I've never bothered removing the grommet before but don't really seem to have this issue (unless someone has already removed the grommet from before). Is this an issue affected across all A4's?

 

[Chris-Vspec]

I know it affects the B6 and 7 not sure about the 5 and 8

 

[ESD1711]

Couldnt tell you a comprehensive list, but I know its across a LOT of different models, Not just A4's and also in to things like Passats and such like too.

 

[razza1]

So why are the grommets there in the first place?

 

[ESD1711]

The grommets DO drain water away to begin with, but over time the become clogged up and stop functioning.


I believe they are there to stop road spray / dirt etc coming up the way but given your inner wheel wells and under tray and such like, I'd imagine the risk that poses to be significantly lesser than that of them becoming clogged and flooding your scuttle.


The only thing I can liken them to would be a cone. Probably about the width of a two pound coin at the top and probably about the width of a straw at the bottom..... So it doesn't take much to block them, and when they block..... They just fill up and become useless.

 

[Wrath]

Last time I tried to shift the battery I nearly put my back out, it ain't easy.

 

[jdp1962]

Last time I tried to shift the battery I nearly put my back out, it ain't easy.

Plus One!

 

[Tiffy]

how did you guys remove the battery in the end???....i want to cxheck mine

 

[jdp1962]

how did you guys remove the battery in the end???....i want to cxheck mine

You have to undo a securing bolt that is positioned on the "floor" of the plenum chamber, front centre, between the battery and the forward bulkhead. It's practically invisible, so you have to remove every cover and all the little ancillary bits and pieces around the battery, then stick your head right up to it and peer down. Then you'll see where it is.

I forget what torx size it is, but use a long bar to get to it, then break your back lifting the battery out.

I checked my plenum chamber yesterday (with the battery in place, that is). No sign of any water at all.

 

[ESD1711]

Yeah the sheer weight of the battery and its location makes it a bit awkward to heave out.

As said though, you shouldn't need to go as far as that to check it. If the plugs are blocked, you'll know just by checking with the battery in place as there will be a build up of water.

If you can't see any water in the bottom of the chamber, you're ok..... For now. Check it regularly though would be my advice

 

[ollie86rn]

Just a note for everyone, I ordered the trims for the plenum chamber from audi and went to pick them up today. At the time I asked about codes for removing the battery for radio etc as obviously needed to disconnect the battery to remove these drain plugs and to my surprise they said they would whip them out there and then for me. They had it about 5 mins in the workshop and was back in the courtyard minus one bung, no need to remove battery! The bung under the main servo was still there but at least the other had been removed, all he seemed to do was jack the car under the engine to gain better access, not sure how but saved me the job! Just got to fit the trims now!