
Dirty air filter on the right, clean air filter on the left. Which would you rather?
Vehicle filters are one of the most neglected maintenance item. Why? Well most of the time the filters are enclosed and thus, ‘out-of-sight-out-of-mind’ comes into play. A good mechanic will inspect all of your filters regularly for you and let you know when they need to be changed.
Why change them & will it make a difference? Most of the time, you will not feel any difference changing the filters. However, if you don’t then you will feel a difference and end up having to replace something other than just a filter.
Each vehicle has the basic 3 filters: Engine Air Filter, Fuel Filter and PCV Valve.
- Engine air filter protects your motor from dirt and other possible particles that would cause it to choke.
- Fuel filter protects your engine from contaminates that might be sent through the fuel lines from the gas tank to the motor.
- PCV Valve allows your engine to release pressure build-up inside the motor called blow-by. This also prevents your oil gaskets from leaking.
Some additional filters include:
- Cabin air filter is for your air conditioning system. This blocks elements in the air that might cause discomfort or damage from getting into the cabin of the vehicle
- EGR Canister or Charcoal Canister absorbs gas fumes from the tank as it vents out of the tank during filling. You can read more information on this function at http://www.type2.com/library/fuel/egr.htm.
Now you know what the basic functions of your filters are, it’s time to explain how it helps your engine. Everything in your vehicle works as a chain reaction. The key sends power the the starter, fuel pump and computer. Starter cranks the motor, fuel pump delivers fuel and computer comtrols how the fuel pump regulates the fuel. In that time, the air filter, fuel filter, pcv valve and canister are all being used. If any of those filters are clogged or dirty; it can cause a restriction in the chain.
An example of what type of difference filters make:
- Fuel filter on average is about $20 for the part; if it gets clogged it can damage your $350 fuel pump.
- Air filter on average is about $15-25 for the part; if it gets clogged it can damage your $250 throttle body or worse your $3000 engine.
- PCV Valve on average is about $2-10 for the part; if it gets clogged can cause your Oil Pan ($150), Valve cover ($100) or Timing seals ($300) to leak
- Cabin air filter on average is about $30; if it gets clogged can cause your evaporator core ($600) to freeze or fail prematurely.
Consult your vehicle maintenance manual or visit your Local Auto Repair Shop to find out if you need your filters changed.

