Cabin Filter - Beware...
I can't believe the previous owner left the car without a cabin filter...
After just finished cleaning the car, I thought it would be a good time to replace the cabin filter. Well, nothing to replace, as the car had it missing.

I can't believe the amount of leaves wedged in where the filter suppose to be:

With the filter snug in there, probably the HVAC will suck in fresh air much happier and free of debris.
After just finished cleaning the car, I thought it would be a good time to replace the cabin filter. Well, nothing to replace, as the car had it missing.


I can't believe the amount of leaves wedged in where the filter suppose to be:

With the filter snug in there, probably the HVAC will suck in fresh air much happier and free of debris.
Not too hard, just get under the passenger's footwell, pop down the panel closest to the front of the car (may be some foam that needs tearing) then locate the panel up towards the center of the car. There is a little black plastic hatch holding it in, lift that little latch and pull the two pollen filters out. On a C6 there are two small ones stacked on top of each other, and make sure you put the new ones in with the air flow arrow in the correct direction.
I looked under there but nothing resembling a replaceable filter was there. Maybe it was taken out and never replaced? I had purchased one but when I found none to come out I thought I had made the error. Though thought it funny that it would not have one. Being an audi novice I let it go.
Beefski,
since your 1996 2.8L model is so close to mine, there's a likely possibility this may help you.
First you need to take the cowl off. It only snaps in four retainers on top of the firewall. (Sorry, I didn't take a pic of that, but you can actually see a retaining metal clip on top of the firewall in the pic)
You should see something like this:

Remove the two T-30 screws in the middle, as well as two at the ends:


Next, you need to remove the wiper arms. Unscrew the nuts (14 or 15 metric - sorry, can't remember) and pop the wipers out.

After you remove the wipers, then the whole grill should come out easily. As it comes off, it exposes better the HVAC unit.
On top of the unit locate the three small nuts that fasten the top cover (if I remember well it is a 3/9'' size. However, I bet you can use pliers.

Pop the cover off and you should be able to see the filter. (As said, on my car the filter was missing, so the pic is with the new filter popped in).
Note: without the filter, you should be able to peak in the passenger side footwell if you flip the vent panel.

If yours is missing as well, you may have to clean all the accumulated debris, but from the inside of the cabin, as you don;t have too much room from the engine bay to reach deep in there. However, to clean from the inside (as I did), you have to remove the glove box...
In the pic you can see the the vent flap portion that covers the cabin's opening:

Another view from the inside (passenger side footwell):

If you need to, you may unscrew the two nuts (same 3/9'' size) holding the flap secured, so you can easily clean from the inside the bottom of filter's frame.

When satisfied with the debris removal (if the case), insert the filter paying attention to the air flow arrows (as auditech pointed out):
and start reinstalling everything back together in a reverse pattern.
Good luck.
since your 1996 2.8L model is so close to mine, there's a likely possibility this may help you.
First you need to take the cowl off. It only snaps in four retainers on top of the firewall. (Sorry, I didn't take a pic of that, but you can actually see a retaining metal clip on top of the firewall in the pic)
You should see something like this:

Remove the two T-30 screws in the middle, as well as two at the ends:


Next, you need to remove the wiper arms. Unscrew the nuts (14 or 15 metric - sorry, can't remember) and pop the wipers out.

After you remove the wipers, then the whole grill should come out easily. As it comes off, it exposes better the HVAC unit.
On top of the unit locate the three small nuts that fasten the top cover (if I remember well it is a 3/9'' size. However, I bet you can use pliers.

Pop the cover off and you should be able to see the filter. (As said, on my car the filter was missing, so the pic is with the new filter popped in).
Note: without the filter, you should be able to peak in the passenger side footwell if you flip the vent panel.

If yours is missing as well, you may have to clean all the accumulated debris, but from the inside of the cabin, as you don;t have too much room from the engine bay to reach deep in there. However, to clean from the inside (as I did), you have to remove the glove box...
In the pic you can see the the vent flap portion that covers the cabin's opening:

Another view from the inside (passenger side footwell):

If you need to, you may unscrew the two nuts (same 3/9'' size) holding the flap secured, so you can easily clean from the inside the bottom of filter's frame.

When satisfied with the debris removal (if the case), insert the filter paying attention to the air flow arrows (as auditech pointed out):
and start reinstalling everything back together in a reverse pattern.Good luck.
Last edited by chefro; Feb 11, 2009 at 05:21 PM.
Oh, if you change the filter, it is a wonderful opportunity to check the water drain hole on the bottom of the firewall.
You should be able to locate it close to the right side bottom corner of the HVAC unit (looking from above the engine bay, exactly the position you replaced the pollen filter from).
I had a bunch of leaves on the bottom of the firewall and the good thing was that all were still dry...
If you have access to a high pressure air hose, it would me much easier to blow the whole bottom of the firewall area.
Good luck.
You should be able to locate it close to the right side bottom corner of the HVAC unit (looking from above the engine bay, exactly the position you replaced the pollen filter from).
I had a bunch of leaves on the bottom of the firewall and the good thing was that all were still dry...
If you have access to a high pressure air hose, it would me much easier to blow the whole bottom of the firewall area.
Good luck.


