The Mazda RX8 comes standard with a cabin air filter, which filters dust, dirt, odours and other particulates out of the air that blows into the passenger compartment through the vents. If you've noticed that your RX8 vents don't blow as hard as they used to or if the air has a bad odour, it may be time to change the filter. The RX8 owner's manual does not include instructions on how to do this, instead urging owners to take the car to an authorised service centre for this replacement. However, you can do this yourself in a few minutes with simple tools.
Empty the passenger side glove box.
Use a screwdriver to gently push the glider arm on the right side of the glove box hatch toward the centre of the glove box. Push it over just far enough for the arm to come off its tracks, allowing the glove box hatch to drop down lower.
Squeeze both side panels of the glove box hatch toward the centre using your hands. You just need to squeeze them together enough to allow the entire hatch assembly to drop forward. Once you clear the sides of the glove box housing with the hatch, let the hatch dangle.
Locate the cabin air filter box in the cavity behind the glove box. It is long, black and rectangular, positioned horizontally with the right edge obscured behind the glove box housing. There is a removable panel across the front of the box.
Remove the panel on the air filter box and set it aside. To get the panel off, just squeeze the plastic tabs around the edge to unlatch it.
Take note of the direction of the air flow arrow printed on the outside of the filter frame in the filter box. Make sure that you install the new filters with the arrows pointing the same way.
Pull the leftmost part of the air filter straight out. The second half of the air filter should be pushed over to the right side of the filter box. Slide it over to the left, then pull it out.
Slide one half of the new filter into the filter box, making sure that the air flow arrow is pointing in the same direction as the last filter. Slide this filter all the way to the right of the filter box once you push it all the way to the back, then install the second half of the new filter, again making sure the arrow is pointing the right way.
Snap the air filter box panel back into place on the front of the box.
Push the glove box back up into place, gently squeezing the sides of the hatch together so that they will clear the sides of the glove box housing. After you get the sides past the housing, use your hand to press the glider arm to the left as you push it the rest of the way into place. The glider arm will snap back into its tracks once the hatch is partially closed.
Cabin air filter replacement is recommended every 10,000 to 20,000 miles, but the real maintenance schedule depends mostly on the dirtiness and dustiness of the environment in which you typically drive. Cars driven on dirt and gravel roads and in other dusty areas will need their cabin and engine air filters replaced more frequently.