Changing the pollen filter, or cabin air filter, in your Subaru Impreza is a maintenance project that you can do in a few minutes with just a screwdriver. The filter, located behind the glove compartment of the car, cleans the air coming in through your heat and air-conditioning system. You cannot simply clean the old filter; you must replace it with a new one, available from your dealer or an auto parts store. Regularly changing out your cabin air filter means purer air for you and your passengers.
Remove the glove compartment from the dashboard. There are seven screws holding it in and one clip that you may need to pop loose. Keep the screws in a safe place so that you can reuse them.
Snap off the filter cover directly behind the glove box.
Slide the used cabin air filter toward you. There are no other retainers, so if it seems stuck, give it a tug. It could have pollen, tar, bugs or almost anything on it that could make it stick a little.
Discard the old filter.
Insert the new filter into the slot behind the dash. Make sure it is all the way in where it belongs.
Install the cabin air filter retainer by carefully snapping it into place over the filter.
Reinsert the glove compartment into the dash, and secure it with the seven screws and the clip you removed. Take a minute and make sure it lines up and fits right.