E36 Cabin Microfilter Replacement DIY
 

All the usual disclaimers apply . . in short, do this at your own risk, blah blah blah. Also, people have different methods of doing this job, and I have mine.

It's recommended that you replace the cabin microfilter yearly. Accumulated dust and debris can lower your climate control's efficiency. Some people find this somewhat difficult to do, but it's not rocket science. Part of the problem is that you need good pictures to describe the operation, and hopefully this writeup will address this.

I'll start with something no one ever shows- you can actually remove the passenger side air vent grilles! This makes it easier to deal with the screws in the vent. Tilt the vent down, then grab it at the top (left photo), and pull out till you feel it snap. Then tilt it up straight (middle photo), and pull straight back. It'll pop right out, as in the right photo:

http://www.unitedbimmer.com/files/ub...sky/micro1.jpg

Now let's head down to the underside of the glovebox, and remove the two screws as shown here:

http://www.unitedbimmer.com/files/ub...sky/micro2.jpg

Once you get those off, open the glovebox door and remove the six screws as shown below. Close the vent ducts before removing the top screws, so they don't fall in accidentally. The middle set of screws have a cover over them; just pry them off to reveal the fasteners. Pull the glovebox straight out. There are a couple of wires connected to it; just unplug them as needed and set the whole thing on the floor.

http://www.unitedbimmer.com/files/ub...sky/micro3.jpg

Next, you must remove the vent ductwork. Disconnect it off the main duct behind the center console; it just pulls apart. The only thing left holding the duct in place is one plastic rivet. The photo shows me carefully loosening it with a flatblade screwdriver. The inset photo shows the rivet after disconnecting the duct.

http://www.unitedbimmer.com/files/ub...sky/micro4.jpg

Next thing to get out of the way is this plastic electrical junction box (not sure what it's called). The arrow in the photo shows a locking tab which you must push in the same direction as the arrow, and the whole box will slide right up and off the bracket. Inset photo shows it off and in my hand.

http://www.unitedbimmer.com/files/ub...sky/micro5.jpg

Now look directly behind the center console and you'll see a knob as shown in the photo below. This is the cover for the microfilter. Turn the knob counter-clockwise about a quarter turn, and the cover will come out.

http://www.unitedbimmer.com/files/ub...sky/micro6.jpg

This photo shows the cover removed:

http://www.unitedbimmer.com/files/ub...sky/micro7.jpg

If you could see back there, this is what you'd find:

http://www.unitedbimmer.com/files/ub...sky/micro8.jpg

You can see the filter positioned vertically, and a tab attached to it (arrow in photo above). Grab that tab, push it toward the front of the car, and slide the filter out. If the filter had ever been replaced before, it will bend in two places, because that's the only way it'll go in or out of the slot with all the crap in the way. Photo below shows what I mean.

http://www.unitedbimmer.com/files/ub...sky/micro9.jpg

Here below is a photo of the new filter next to the old . . yuck. You'll see thin break points on the frame, where you can snap the thing into 3 sections, just like the old one.

http://www.unitedbimmer.com/files/ub...ky/micro10.jpg

Now feed the new filter in through the slot, bending at the snap points as needed to get it in. Seat the filter by pushing the tab toward the rear of the car. If you don't do this, the cover will not go on properly and you won't be able to lock it on with the knob.

Putting everything back together is simply the reverse of removal. Don't forget any wire harnesses you may have disconnected off the glovebox. Changing this filter will loosen dirt and other crap that was in there, so stand back when you turn the blower on for the first time . . stuff will fly out of the vents! Now take a long drive and enjoy the fresh air :)

Thx man, but removing the glovebox is not necessary: http://www.bimmerwerkz.com/forum/mai...html#post91484

^^^You're right, I know everybody does it that way, but I have to argue that there is a right way and a wrong way. Once or twice is fine, but if you tug on that vent duct like Furious did enough times, that plastic tab will break clean. It's the only thing keeping the ductwork in place.

People should be mindful that there were production variations with the glovebox, for example, my 325i, production date of 02/95, has an 8 or 10mm bolt securing the glovebox to a bracket about midway on the top. You can drive yourself :bdances tugging at the thing after removing those six screws. If I remember correctly, those screws aren't all the same length, either. One more quirk with these things...

Touché. I just do it the "wrong way," but with care :p

Chrys, thanks for doing this. It's one of my small projects for the summer. I had no idea where the stupid thing was.

:shades

I do it with every oil change (6000 miles or six months) and it always comes out looking like it needed changing badly.

where is the carbon microfilter on an x5

Just to add to the DIY, for all those with a right hand drive bimmer, your microfilter is on the drivers side. So instead of having to remove the glove box just remove the three screws under the steering wheel which holds the kick panel in.

i just did this micro-filter thing. my production date is 01/95, and yea i think thats what it is, i just couldn't get the glovebox out. where is this bolt you speak of? lol, well, either way, i ended up removing the passenger underpanel and i had to remove the floor ducts in order to get the stupid thing out, and it was still a pain, well either way its done now....

2/95 production date as well. I think you'll find that 10mm bolt under the glove box light, so once you take that out that's where you'll find it, attached to the bracket, if memory serves me... The job is still a p.i.t.a. in my book though...

^^^You sure that bolt has nothing to do with the sagging glovebox fix?

wait, what is the sagging glovebox? now that you mention it, well i took those 6 screws out and started fooling around, but when i put everything back together i noticed that there is a little gap between the glovebox door and the vents on top, now i dont know if it was always like that, i rarely ever ride in the passenger seat

oh, and the ac is just tons better, lol :)

http://www.understeer.com/glovebox.shtml

^^^The basic idea. Some people use screws, some use bolts further in.