One of the easiest DIY projects you can do on your car is swapping the cabin air filter. It’s very inexpensive to do yourself and doesn’t require more than a very simple socket set. On this BMW 335i, you would save about $100 by not going to the dealer and doing this at home. In the video, I show you where the filter is located, how to remove it, swap it for a new one and reinstall the plastic bracket back on the car.