Is this common knowledge?


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Oct 15, 2012
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Hi, I'm pretty new on here but I just discovered something about my air inake you may or maynot know about. Mine has a full service history and the air cleaner was changed fairly recently. I was having a look around trying to spot a coolant leak - see my other thread please if you are able to help, and ended up taking out the ducting leading from the grill to the air box. When I was reassembling I noticed a thin gauze mesh halfway down one of the pieces of duct which was clogged absolutely solid with fine dust, looked like years worth. At service the mechanic has either not known about this or hasn't bothered cleaning it out. I did clean it and am amazed in the difference in acceleration, it was mapped a few months back which made a big difference but cleaning this mesh feels like it's been mapped again, on a par with a mapped/sportcat subaru gb270 Wagon I used to own. Apologies if I'm preaching to the converted but It could be easily overlooked and effectively blocks the air intake, worth a check imo.
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any pictures would be great
take the mesh out
the service lads usaly do
Is it before the MAF? If so it's to maintain equal flow around it.
Is it before the MAF? If so it's to maintain equal flow around it.

Yes it is; it's in the join between two sections of inlet pipe, just behind the offside headlight. I discovered mine when changing a headlight bulb; cleaned it and put it back.
Yes it is; it's in the join between two sections of inlet pipe, just behind the offside headlight. I discovered mine when changing a headlight bulb; cleaned it and put it back.

sounds like the best option to me!
My 2005 doesn't have any mesh in the snorkel part. The top of the air filter box has a thick plastic mesh stopping stuff going into the pipe. The heat shield is attached to the base of the air filter housing but the whole thing lifts out i.e. don't try and unscrewn the heat shield.
To be honest, the entire inlet system of the 2.0 tdi is incredibly asthmatic! I've been tempted to change it, then wake up and realise its only a commuter car.
Had exactly the same experience, had the car recently serviced at a local independant, and paid extra to have the filter changed, as it was,nt due, but as the car was new to me I thought I would, trying to change my sidelight bulbs to LED recently I had to remove the air intake and the plastic filter insert in the "snorkel" part of the intake was almost completely blocked, with a black dust which seemed to be encrusted on the mesh, I cleaned it and put it back in place, though I did,nt partculary notice any performance increase though it does seem to be slightly better on fuel now.
Sorry, my PC is kaput, not got a clue how to post pics from the ipad, it's pretty easy to find though, I unscrewed the 2 bolts at the front and the 3 sections of duct came apart quite easily, it's easy to spot after that and just pops out for cleaning. I used the hoover but it looks as if it may be designed to be washed out, it will dry quickly. Mine is the 3.0tdi, not sure if he setup on the 2.0 is the same.
I can't find this on mine, 2.0 tdi BRD 2007.

I took out the plastic duct that goes from the grill to the air filter - 2 sections.
I know this might be going off on a tangent on this thread but do any of you have this fitted on your air intakes. It sits at the top of the intake. Not sure if this would prevent what you have experienced. I have it fitted to mine....suppose to be for ice and snow and stuff for IKEA land I guess.
Audi B7 A4 FWD 2.0T > Engine > Intake > ES#436254 Cold Weather Pre-Filter - 8E0129054

Yes I have this on mine. I thought this is what this topic has been about all along?
Guys ideally you all need to replace this filter as I saw this thread and wondered if mine had one. I've not had my car very long so I thought I'd just check the air filter condition aswell. I noticed that the pre-filter had also been taken out of mine, which I wasn't too bothered about, but when I checked the main air filter I noticed that I'd had a mouse nesting inside. So although it may seem useless, Audi must have put the pre-filter inside to stop this sort of thing happening. So I'm just gonna replace mine and check it from time to time.
This was a life saver for me.. When I flooded the car last week that filter stopped all the crap flowing straight into the air filter.. When we took it apart all the leafs and mud etc got stuck there. I washed it all out left it to dry and put it back in.

All I was left with was a sodden/clean :) air filter..

Worth having I would say


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Recycling a 7 year old thread!
Air intake pre-filter mesh, reading above I'm wondering if these are on 3.0tdi only.
Mines looking tatty so I've ordered a replacement.
It's tempting to remove it, but it does stop leaves & insects cluttering up the air box, however it does need regularish cleaning, which makes me wonder how that went with extended servicing?
Does anyone know the purpose and why it's called a 'cold weather' filter?
Better with, if maintained, or better without?
My cars back together so here is a web photo showing the filter clipped into the end of the induction tube where it clips onto the air box.
Part No. 8E0129054


  • Air pre filter.jpg
    Air pre filter.jpg
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