This is a DIY for replacing the air filter on an M3 CSL written by Tom from New Zealand.
- Recall notice No: 0013610100
- Old filter part no: 13 72 7 833 644
- New filter part no: 13 72 7 838 625
Now for the differences between the new and old filter - Notice in the picture below the extra band of black foam on the underside of the filter element. This stops debris and the likes from getting past the filter in the bottom right corner of the box.
1. Remove strut brace by undoing 4 x 13mm nuts (circled in blue)
2. Remove 3 sensors and 1 vacuum line (circled in red in pic above). These are quick release sensors, so just push down on the spring release and pull.
3. Remove pollen filter and filter tray altogether. This is done by removing the lid covering the battery wiring harness (just pry open carefully - circled in yellow just above the box) Once the lid is removed just pull away the battery and sensor harness) Turn the 3 clips (circled also in yellow) anti clockwise to open the pollen filter lid. Once the lid is removed pull out the pollen filter element.
4. You will now see 4 x T30 Torx bolts (circled in red above) holding the pollen filter tray to the firewall. Undo these and pull the whole tray up and away from the car. Don't worry about the rubber seals, they will slide back into the tray quite easily.
5. Now you are ready to remove the box - I found it easier to take the SMG hydraulic fluid reservoir out of it's hoist for bit more room to remove the box, but it is not absolutely necessary if you don't mind some scratches on the carbon box. To remove the airbox you will need to undo 4 x T25 Torx screws (circled in blue above) Once removed pull the box up by lifting the front side. There are 3 guiding pins for the box (circled in yellow).
NOTE: The trumpet side of the box is connected to 2 intake tubes (see pic below)
These simply slide out of the intake pick up tubes behind the bumper - they are not secured in anyway or form, so just pull the whole trumpet side of the box out. It is a tight squeeze, just be patient and be careful - you will not damage or scratch anything.
Once removed you will see the filter element. Remove the old element and clean out the airbox (yes it will be quite dirty as the old filter doesn't seal properly especially around the bottom right edge.)
Insert the new filter - it is quite a tight fit, because the filter itself is slightly longer and has the black sealing foam on the bottom to help it seal and seat in the box a lot better.
Reinstall box in reverse.
Special note: The trumpet side of the box is quite hard to get back in - be patient, but line up the 2 intake tubes first - the smaller tube is harder to line up.
PS - for those wondering where the manual oil dipstick is - I forgot to take a photo of it - but it's roughly where the yellow arrow is in the picture above. It's very short so don't pull too hard.