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Subject: Today's a good day to change the microfilters under the hood: How To Do It Author: DavidC (moderator) : member since December, 2003 : 11220 posts Posted on: 2004-04-04 18:21:57

It must be because its springtime and its a good day nationwide to work on our cars. For some reason, today I received several different email messages all asking about how to replace the charcoal microfilters under the hood. This isn't something I'd actually done myself yet, so it was a good opportunity to take some more photos and post it here on the board for everyone.

The bottom line is that its really simple. All you need is a philips screwdriver and five minutes.

FYI, you should probably change the filters once a year or every 15,000 miles. I believe the cost is around $60 at a dealer (much more if you have them do the installation). I'll find out tomorrow.


The two charcoal microfilters are located on the underside of the hood, near the windshield on the left and right.


A closeup of the driver's-side microfilter housing.


The filter housing is a door hinged on the left in this picture. A single philips screw on the right side is all you need to remove. Don't let the door fall down and scratch your engine cover.


Opening the door to reveal the dirty microfilter.


Another view of the microfilter in the housing.


Depress the metal tab on the right side of the microfilter to remove it from the housing.


The dirty microfilter after removal.


The empty housing where the new microfilter will be inserted. Now's a good time to clean it.


Another view with both microfilter doors opened.

David Cecil
'97 740iL, 119k miles
'86 735i, 91k miles
'77 320i, 140k miles

www.e38.org has links for everything about your BMW 7-series automobile

• Today's a good day to change the microfilters under the hood: How To Do It (pic) - DavidC 2004-04-04 18:21:57 (39728 views)
  • Here's a shot of the old and new filter, side by side (pic) - DavidC 2004-04-05 18:12:56 (5899 views)
  • I thought this was a difficult project -- this looks easy! (nt) - pogophil 2004-04-04 22:16:46 (2015 views)
    • Are you thinking about the re-circ filters under - sealbeach740 2004-04-06 16:13:13 (3891 views)
  • remember to buy the filters first...the car is not to be operated without the (pic) - filters in place....Q 2004-04-04 18:58:36 (4709 views)
    • good point (nt) - DavidC 2004-04-04 19:06:48 (1933 views)
    • What brand monitors are those? (nt) - johngoga 2004-04-04 19:02:13 (2305 views)
      • oops! that was not the pic I wanted to post...those where bimmergirls - Q 2004-04-05 11:36:38 (2858 views)