How to Change the Air Filter in a BMW X3
This a detailed guide on how to change your engine air filter in a BMW X3. The car in the photos is a 2006 model but the process is the same for any year, and for that matter, just about any late-model BMW crossover or car. Only the accessibility of the air box under the hood, the filter type, and the clip locations will vary.
This job should only take about 10-20 minutes and does not require any tools. Ordering your filter online (links below) and replacing it yourself will save you money and keep your engine breathing nice clean air.
This really should go without saying, but just in case: never do this with the car running.
1) Working around the sides of the air box, unclip each of the clips holding the top to the bottom of the airbox.
2) With the clips loose, you can then lift up on one side the air box top to separate the halves. You can then access the air filter. Lift it up and slide it out. Note that air flow comes in the bottom of the box, through the filter and out the top and into the engine. Thus below the filter is the dirty side and the top is the clean side.
3) Use a rag or a vacuum to wipe out the dirt in the bottom half of the air box. The top half of the air box should be clean since only filtered air reaches it, but if you see any dust there at all go ahead and clean it out.
4) Install the new clean filter back into the air box. Make sure the soft foam seal is at the top and the longer paper part of the filter is down. The foam seal should seat easily into the bottom half of the airbox. Close the top half of the box making sure the seal all the way around is seated properly and not being pinched or crimped anywhere.
5) Re-attach each of the clips all the way around the air box so it once again forms a nice airtight seal between the top and bottom halves.
Grab yourself a beer and toast a job well done and feel good knowing your car is now breathing freely again with good clean air.
How Often To Change Your Air Filter
This depends on your driving conditions but it's usually recommended to change the filter every 30,000 miles. If you drive off road or in dusty conditions you may want to check your filter more often. I replaced mine 8 months ago (about 10,000 miles) and I'm pretty surprised at how dirty it is already. Given how relatively cheap it is to replace I probably will be changing mine every 20,000 miles or so.
Air Filters and Ordering Online
It's easy and cheap to order new air filters online and I order mine from Amazon. They provide a nice fitment tool so that you can enter the year and model of your car to make sure you get the filter that fits your car. Note that there is a difference between the filter for 2004-2006 and 2007-2010 models.
Here are some links to some good OEM German air filters.
2007-2010 X3 Air Filters
Mann is also a good German OEM air filter. This should fit your 2007-2010 X3.