There are a number of replaceable filters in a car. They are listed in your ownersmanual along with recommended replacement intervals. If you live in a dusty area or in abig city, then you should replace them more frequently. The following filters are commonto most cars
Air filter: used to filter the air going into an engine. This filter is usually easy to replace yourself.
Fuel filter: found either in the engine compartment or near the gas tank. This filter is best left to your auto mechanic to change.
Breather: works with the PCV valve to allow clean air to be drawn into the crankcase to purge moisture and acids from the engine.
PCV Valve: works with engine vacuum to draw fumes from the crankcase and burns them in the combustion chamber.
Cabin Filter: on a number of late model cars since the early '90s, there is a filter in your air conditioning system that cleans the air before allowing it into the passenger compartment. These filters are usually somewhere under the dash. Your owner's manual will tell you if you have one and where it is.
Check your owner's manual for any other filters requiring servicing.