So, after many months (like 24) of having a progressively worsening musty damp smell coming into the van that could only be prevented by turning on the air con. I'd replaced the cabin filter and that wasn't it so i had to look deeper.
there didn't seem to be much info kicking about for issues without the air con being on, some on the golf forum but lost were about the filter and other odd theories. I found some vids on products you can mist through the system to cover smells and stuff but that's all $$, lysol seems to be a product but no available in aus.
So I started looking, pulled the bonnet vent off under the windscreen and stuck my hand in, yuk.. there was 1/2 an inch of slime, crud and fully wet damp composted organic matter in the section where the air come in.. hmmmm.. cleaned this out and washed it. then decided to squirt some cleaning vinegar and eucalyptus mix through and then squirted some mould killer in there for good measure with the system on full blast..
problem solved! actually pretty chuffed as its been annoying me for so long but because its been hot I'd kept the air con going.
so, basically the area above the battery where the intake is gets full of sh*t and stinks. good to know. its probably mentioned here somewhere but i couldn't find it.
also, when pulling the cabin fliter tons of crap comes out and I'm sure a better big finer mesh cage over the intake would solve that issue so I'm going to make one out of chicken wire and wedge it on there.
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