That sounds like an air filter for the passenger compartment
In the firewall. Between the engine compartment and the passenger compartment
In the front of the engine compartment , on the passenger side , inside the engine air filter housing
try looking under or behind the glove compartment in the passenger side
The cabin air filter on a 2003 Chevy 2500HD pickup is located on the passenger side under the glove compartment. To replace it, first remove the two screws on the kick plate under the glove compartment. Remove the kick plate. Then, unclip and swing the filter housing cover to the right. Remove the filter by pulling straight down. Insert the new filter, and reassemble in the reverse manner.
passenger side look under your compartment you will see a cap take that off and replace it
It Located behind the glove compartment. Just squeeze the sides of the glove compartment and it will release and hang down. simply open the cabin filter compartment and change filters.
I was looking at the 2003 Ford Explorer Sport Trac Owner Guide and it does not show an air filter for the cabin / passenger compartment , so I would say ( No )
Under the hood, on the far passenger side in rear of engine compartment in plastic air intake plenum.
See Passenger Compartment Air Filter on page 3-26 of your "Owner's Manual", under Section 3: Instrument Panel - Climate Controls.....
To change the cabin filter on a 2003 Ford F-150, first, locate the filter housing, which is usually behind the glove compartment. Remove the glove compartment by detaching the stops or screws, then pull it down to access the filter cover. Take out the old filter, ensuring to note its orientation, and replace it with the new filter, making sure it’s installed correctly. Finally, reassemble the glove compartment and ensure everything is securely in place.
In a 2003 Toyota Hilux KZ-TE, the cabin air filter is typically located behind the glove compartment. To access it, you'll need to open the glove compartment and remove any contents, then detach the compartment by releasing the stops on either side. Once the glove compartment is lowered, you should see the filter housing, which can be removed to change the filter.