How to install the OEM SP23 Cabin Air filter in a regular Mazda 3. (and/or diffuser)


Mazda 3
Ok, I decided to install the air filter to my car because it helps clean the air, and it make your air conditioning colder because of the built in diffuser if you have a 2004 model. (2005's & up already have a diffuser)

Here's the steps to do it yourself.

First, Order the filter(part # BP8P-61-J6X) from

It took about one and a half weeks to arrive via DHL.

You'll need a #2 screwdriver, 12mm socket wrench, and a knee pad(if you're a wuss like me).


Start by removing the plastic kick panel under the glove box by just pulling down, the out.,then the panel to the left be removing a retainer clip.

****Optionally, you may Take out the glove box by uncliping the dash strip and unscrewing the 2 screws obviously holding it in. The rest is tension clips, so just pull on the glove box and it slides right out. You'll have to pause and unscrew the light at the top. This will let you see A WHOLE LOT BETTER. and also give you more room with the screw driver later.

Next, Undo the wire harnesses that are attached to the white junction box. You must swing back the black levers on each of them for them to come loose. After that you must twist the white clips to swing down the junction box and remove more harnesses from the top.

Now wiggle out the junction box as it shouldn't have anything else attached to it. Then un bold the 12mm nuts(2) that hold the bracket on that the junction box was being held by. And swing it a little to the right to clear room.

Now, Unclip the grey wire on the left, and unscrew the 4 screws closing the air filter area. And swing it out of the way.

****Optionally I reccomend you get a vaccum and clear out any dust and debris that might be stuck in the hole.

Now slide in the first piece of the filter to the left hand part of the hole vertically, and then slide it up. Hold it there as you wedge the second piece in the same spot underneath the first. They include a piece of paper with a great diagram of which piece goes on top.

after it's settles in correctly, place the cover back on , re-screw all 4 screws and remember to reconnect the grey wire.

Now remount the bracket that holds the junction box.

Reconnect the wire harnesses that go into the top of the junction box

close the junction box

Reconnect the Bottom wire harnesses.

****Make sure you push hard on these two harness' black levers... They feel tight at first, but they'll throw a Check engine light, so make sure they're extra extra tight!!!

Put the Plastic kick panel and side panel back on

**** If you took out the glovebox, make sure there are no wires in the way and slide it back in. Remember to reconnect the light at the top. Also, hit the glovebox a few times to make sure the retention clips lock in plase. I also used my fingers on the weather stripping to make it seal a little better. Screw it back in, and replace the dash strip.

Now, Sit in the drivers seat, Turn on the AC and enjoy the clean fresh air!!

If your Check engine light comes on, go check your wire harnesses and tighten them up. To reset the light after you fix them you have to turn the car on and off 2 or 3 times.

****Optional: Give yourself a pat on the back. Great job.

LOTS of props to notorious5, MZ3-BK3P, and raven. Their pix and walkthough were a bunch of help, and they inspired me to do this full walkthough with pix.
Last edited:


mazda3 5 door
props on the walk through... though can't you go complian to your stealership and get that done for free b/c of a tsb about it???
Quick question. I just replaced this filter myself. Now the info display is giving me the ambient temperature in celcius instead of farenheit. Is there a way to set this back to farenheit?


Turd in the punch bowl
2004 Mazda3s Hatch; 269,000 miles
I think somebody has discussed this before. Try searching. I don't have an ambient temp display, so I can't help.


Registered Know-It-All
2008.5 Mazda3 Hatchback Touring AT, Copper Red Mica
^ Hehe.. Or maybe a BMW forum. (Check the valve cover on the engine.)

Latest posts