Passat B5, B5.5 plenum drain cleaning

[Rob69]

Excellent info Col.
Cheers!

[defever]

Great update, thanks very much BigCol!

I removed the rubber bits in winter 2014. Few months later I upgraded the scuttle to the facelift version (the pollen filter is covered alot better than just the gutter rail) with plenum and battery cover that goes across the width: Scuttle and battery Phelum covers.

I recently removed the battery to do other jobs so I had a quick check; no muck and very dry all around. I don't think I'll do the seals for ECU and pollen filter boxes, as I am confident that any water coming in will pass through the two holes and the plenum cover minimises any foreign object blocking up the space.

I think the facelift scuttle and plenum covers for Passat are the same as B5 A4 so if you get hold of these parts then it might be a good option to consider (unless you want to keep yours all original set up).

[Col]

Interesting.

The B5 Passat pollen filter cover was more complete than the B5.5 where the 5.5 relies on a top cover over the plenum and the diverter bridge.

Either way though the issue is with the design of the gasket and placement of the housing. As can be seen there is a lot of cack built up at the back. What happens is the water off the far egde of the screen goes down and gets trapped by the cack. It can only drain away slowly. The gasket is a terrible design and wicks the water through onto the internal / additional sponge liner.

This is a separate issue to the plenum drains which are much lower. You can get this pollen filter housing issue despite the plenum drains being clear as there is another water trap to the back of and to the wing side of the pollen filter housing.

It is a one-off job on these gracefully aging cars but something that needs to be done.

[defever]

Thanks BigCol for further insight!

Perhaps I should check at some point, but I'm not getting any wet carpet or heavy condensation in the morning so I'm assuming there's no water leakage into the car.

I'll bear it in mind, and I'd like to hear from fellow B5 / B5.5 owners on their thoughts or experiences.

Great thread on a great forum!

[Charliedog]

Hi Col, Thank you for a very informative and graphic displlay on how to clean the drain plugs. I am a newbie to this site so just learning where and how to post. Charliedog

[GrantLDN]

Going to have a crack at this later on this weekend. Although I do have a receipt from VW for have some of this work carried out but that was a few years back.

[mjb2012]

Any chance of the pics for these? thanks