If the air coming out of your A/C vents doesn't smell so fresh anymore or doesn't blow as hard, you probably need to clean or replace the HVAC system's cabin air filter element.
Getting to the filter is a little more involved than our Toyota Corolla where you just have to drop the glove box, but the whole process only takes about 15-30 minutes. You'll need a Phillips head screwdriver and a small flathead screwdriver.
Here's the guide -
If the old filter isn't too dirty save yourself some money and just tap out the bugs/leaves/dirt and blow out the dust with a shop vacuum.
-Paul