Think twice.
It's an enormous pain in the ass.
Don't get me wrong -- it's a simple procedure.
But the filter is under a panel in the passenger footwell behind a vent and the filter cover is both clipped in and screwed in. Worse, the slot the filter goes in is curved. Clearly, the engineer who designed it never had to replace it.
It's all about positioning. On the ground (as I did it), you really can't get enough room even with the seat all the way back to really get a good angle on all the fasteners. I imagine it wouldn't be any better in the air on a lift.
I'd recommend you try it yourself at least once because I got news for you: the guy at the BMW dealer (who wants $200 to replace a $35 filter) is never gonna put all those panels and fasteners back the way you will.
For those game for the challenge :-), here're the ITSA instructions.
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03-04-2026LAST POST
05-24-2021
05-24-2021
M40i4me
,
spangle1980
+12
05-24-2021
05-24-2021
Just did this. Can confirm that I miss how quick and easy it was in my Accord. The following day my back was sore from a cranky muscle. However, I'll keep doing it because I'm cheap about DIY's, and I'll be damned if I'm going to pay $200 for the dealer to change what I can buy off Rock Auto for $20.
eyescream
,
AlekSC
,
onyxbfly
05-24-2021
05-24-2021
Thanks, saved this for future reference...
05-24-2021
05-24-2021
and it is so easy on my 2011 328!
05-24-2021
05-24-2021
Thank God these are free of charge (parts & labor) in Canada...
FutureTrunks_M40i
05-25-2021
05-25-2021
Whew! My back's hurting thinking about doing it.
Wish it was under the cowling in the engine bay, like on my old E90....
Wish it was under the cowling in the engine bay, like on my old E90....

05-25-2021
05-25-2021
They charge $200 because the mechanic needs to go for a few chiropractic sessions after the change. LOL
Alias1431
,
eyescream
,
Chief Orman
+5
05-25-2021
05-25-2021
OP - I know you didn't (may not have?) meant it - but that initial statement actually made me 

05-25-2021
05-25-2021
spangle1980 wrotehaha...yes when I re-read the OP the first 3 lines sound somewhat 'medical'!OP - I know you didn't (may not have?) meant it - but that initial statement actually made me

05-25-2021
05-25-2021
In all of my previously owned make and models of cars I've only changed the cabin air filter ONE TIME (maximum) and usually not until the car is at least 4 years old or around 60,000 miles..... it's the one item I seldom "go by the book".
05-25-2021
05-25-2021
satz wroteThat was simplicity itself -- open the hood, remove the torx screws and there it was!Whew! My back's hurting thinking about doing it.
Wish it was under the cowling in the engine bay, like on my old E90....
05-25-2021
05-25-2021
Not that bad...
Alias1431
,
Drexel_Lake
,
Chief Orman
+5
05-25-2021
05-25-2021
^Used this very video.
FutureTrunks_M40i
05-26-2021
05-26-2021
Fast400 wroteIf you watch the video, you can see how cramped and poor the working angle is.
Not that bad...
05-26-2021
05-26-2021
Yobyot wroteIt's literally 2 T20 screws and a kick panel that's in the way. That's it. You don't have to take anything else out.Think twice.
It's an enormous pain in the ass.
Don't get me wrong -- it's a simple procedure.
But the filter is under a panel in the passenger footwell behind a vent and the filter cover is both clipped in and screwed in. Worse, the slot the filter goes in is curved. Clearly, the engineer who designed it never had to replace it.
It's all about positioning. On the ground (as I did it), you really can't get enough room even with the seat all the way back to really get a good angle on all the fasteners. I imagine it wouldn't be any better in the air on a lift.
I'd recommend you try it yourself at least once because I got news for you: the guy at the BMW dealer (who wants $200 to replace a $35 filter) is never gonna put all those panels and fasteners back the way you will.
For those game for the challenge :-), here're the ITSA instructions.
AlekSC
,
hotwasabipeas
+2
05-26-2021
05-26-2021
freshxdough wroteTechnically, it IS extremely easy. Not hard at all. It just fucking hurts. You need to contort yourself into this weird angle for periods of time. Skill? 2/10. Inconvenience? 6/10.It's literally 2 T20 screws and a kick panel that's in the way. That's it. You don't have to take anything else out.
Fast400
,
That70sGADawg
05-26-2021
05-26-2021
It's better lift the car while do the service, but as I know my dealer do that like most of us at home. 

Alias1431 wroteTechnically, it IS extremely easy. Not hard at all. It just fucking hurts. You need to contort yourself into this weird angle for periods of time. Skill? 2/10. Inconvenience? 6/10.
05-26-2021
05-26-2021
Did it and couldn't complain. Fairly easy compared to my former Audi RS3 with lowered Bilstein suspension where you need to lay down flat on the floor besides the car. 

05-27-2021
05-27-2021
Worst part about it is if you accidentally end up pushing the recirculating flap past it's end stop resulting in poor air flow and even a slight air resistance/whistle that can be heard during fan operation. Ask me how I know because I did it last week when I serviced my microfilter. I've done thousands of micro filters and the G01 apparently is the only one you can possibly do this with. Yesterday I had to remove the complete glove box, passenger knee airbag and the blower fan to be able to access the flap and flip it back over. This is a known issue and there is an SIB for it. According to the SIB replacement of the complete air conditioning box is necessary. I wasn't about to take my car back to my own dealer for that lol.
CRuben09
,
Douggie
,
ckbingge
+8
05-27-2021
05-27-2021
freshxdough wroteWhat are the odds of finding your post? So, 2 weeks ago, under the regular maintenance, the service center replaced the microfilter. When I picked up the car, I immediately noticed that the fan blower wasn't as potent as before, and a whistling noise could be heard when turning on/off the A/C unit.Worst part about it is if you accidentally end up pushing the recirculating flap past it's end stop resulting in poor air flow and even a slight air resistance/whistle that can be heard during fan operation. Ask me how I know because I did it last week when I serviced my microfilter. I've done thousands of micro filters and the G01 apparently is the only one you can possibly do this with. Yesterday I had to remove the complete glove box, passenger knee airbag and the blower fan to be able to access the flap and flip it back over. This is a known issue and there is an SIB for it. According to the SIB replacement of the complete air conditioning box is necessary. I wasn't about to take my car back to my own dealer for that lol.
Is that flap located at the top of the microfilter housing? I found the one for the outside air which is I believe on the back side. I had to manually force it, so I could get more air, but if I press the recirculating button it doesn't do anything. Can you explain step by step what you did? If you can of course.
Thanks!
05-27-2021
05-27-2021
CRuben09 wroteStep by step was described in my previous post. If you remove the micro filter and look up inside the housing you will see the flap that is sitting incorrectly, like my first photo.freshxdough wroteWhat are the odds of finding your post? So, 2 weeks ago, under the regular maintenance, the service center replaced the microfilter. When I picked up the car, I immediately noticed that the fan blower wasn't as potent as before, and a whistling noise could be heard when turning on/off the A/C unit.Worst part about it is if you accidentally end up pushing the recirculating flap past it's end stop resulting in poor air flow and even a slight air resistance/whistle that can be heard during fan operation. Ask me how I know because I did it last week when I serviced my microfilter. I've done thousands of micro filters and the G01 apparently is the only one you can possibly do this with. Yesterday I had to remove the complete glove box, passenger knee airbag and the blower fan to be able to access the flap and flip it back over. This is a known issue and there is an SIB for it. According to the SIB replacement of the complete air conditioning box is necessary. I wasn't about to take my car back to my own dealer for that lol.
Is that flap located at the top of the microfilter housing? I found the one for the outside air which is I believe on the back side. I had to manually force it, so I could get more air, but if I press the recirculating button it doesn't do anything. Can you explain step by step what you did? If you can of course.
Thanks!
I chose to try and flip the flap myself. You will need to remove the glove box with T20 torx bits. Then also remove the 3x T20 screws on the air box that are installed straight up and remove the blower fan. Then you should see what my 2nd and 3rd photos are. I had the ignition on just so there was power going to the flap motor just so I wasn't pushing against an unpowered flap. I flipped it around almost a whole 180 degrees then turned off the ignition. Turned it back on and selected and deselected recirc and watched the flap work normally again. Drove to and from work today and it's working normally now.
CRuben09
,
ChuckM40i
+4
05-27-2021
05-27-2021
If it's possible to push the recirculating flap past its end stop in one direction, shouldn't it be possible to pull the flap in the reverse direction to restore it to the correct side of the end stop? Perhaps using a suction hose to "grab" the flap so you can pull it.
CRuben09
,
Taiga2002