The blower housing has a Cabin Air Filter that cleanses the air before it gets into the passenger's compartment. In models from 1999 through 2005, the glove box can be opened and the assist cord at the right side released to remove the Cabin Air Filter. Push both sides of the box inwards to lower the glove box door downwards. The light wiring is disconnected and filter door knob turned anti-clockwise to release it. Lifting off the cover reveals removal of an upper Cabin Air Filter element followed by a lower one. Installation is just like removal, but ensuring that the grooves match up with lugs on filters' edges. For 2006 and later models, open up the glove box. On 2006 and earlier models, each rubber bumper is pulled out from each side of this box. On 2007 and later models, turn damper counterclockwise and take it out. Release hinge pins then let your glove box fall open completely. Pinch release tabs on filter housing; pull filter rearwardly away from its location thereon. Installation is once again reverse of removal.