My what what filter? Many, but not all, late model vehicles come with a cabin air filter which filters the air circulated by your HVAC (Heating, Ventilation, and Air Conditioning) system. These are usually located behind the glove box or at the base of the windshield under the hood. You can check your owner’s manual or Google it to find out for sure.
This particularly clogged filter (the dirtiest I’ve seen so far) was in a 2005 Toyota Camry and it had obviously become a nest for a rodent of some kind.
Most of the time, the filter is simply clogged and needs to be replaced, but there was so much junk built up on this one that I had to use some long needle nose pliers to pull out some of the larger crud.
After the pliers, I took a scrap of 5/8″ heater hose and duct taped (OK, it’s actually Gorilla Tape) it to the shop vac to get the rest of the mess out of the blower motor.
The blower motor is the fan that circulates the air in your car, so if something drops down in it, the blower motor may need to be removed to extract the offending element or you could cause damage to it. Or to your face if the blower motor manages to blow the plastic army man out through the vent on the dash.
These cabin air filters sometimes contain activated charcoal to reduce not only particulates in the air, but also offensive odors (like a pungent aroma emanating from your great Uncle Larry).
Now go check your cabin air filter!