The engine air filter lives in the black plastic air box at the end of the big intake hose. Open the clips or screws, note which way the old filter sits, drop the new one in the same way, and close the box so it seals all around.
Your engine breathes a lot of air, and the air filter is what keeps the dirt out. A clogged one will not usually leave you stranded, but it is cheap, it is easy, and it is a great first job where you open something up and close it back.
Some cars need a screwdriver. Many need nothing at all.
What You Need
- The right air filter for your car
- A screwdriver or small socket, only if your air box uses screws
- A shop vac or a damp rag
- A flashlight
Safety First
- Do this with the engine off and cool.
- Do not run the engine with the air box open or the filter out.
- Do not pull on wires or connectors attached to the air box or intake hose. Unplug a sensor only if you have to, and plug it back in before you start the car.
Is the Old Filter Done?
Hold it up to a bright light and compare.
Step by Step
Get the Right Filter
Look up your year, make, model and engine at the parts counter or in the manual. Filters that look close are not always the same, so match the part number.
Find the Air Box
Open the hood and follow the big plastic or rubber hose that runs from the engine to a black plastic box. That is the air box The black plastic box at the end of the big intake hose. The engine air filter lives inside it.. On many cars it sits near the front corner of the engine bay.
Open the Lid
Release the metal clips around the edge, or remove the screws. Keep screws in a cup so none fall into the engine bay. Some lids lift up. Others stay attached to the hose and just tilt open.
Note How the Old Filter Sits
Before you pull it out, look at which way it faces and how the rubber edge sits in the groove. Take a phone picture if it helps. Then lift it straight out.
Check It and Clean the Box
Hold the old filter up to a light. If light barely passes through and it is gray or packed with dirt, it was due. Vacuum or wipe out leaves and dust from the bottom of the box. Do not push any dirt into the hose that goes to the engine.
Drop in the New Filter
Set the new filter in exactly the way the old one sat. The rubber edge should sit flat in its groove all the way around, with no folds or gaps.
Close It and Check the Seal
Put the lid back on and close every clip or screw evenly. Do not overtighten plastic screws. Look all around the edge for gaps. A gap lets dirty air sneak past the filter. Make sure any sensor you unplugged is plugged back in.
Start It and Listen
Start the engine. It should idle like normal. If a warning light comes on, or you hear a new whistle or hiss, shut it off and recheck the lid and any connectors.
When to Stop and Call a Pro
- There is oil inside the air box or on the filter. That can point to an engine breathing problem.
- You find chewed material, nesting or droppings. Rodents may have damaged wiring too.
- A check engine light comes on after the swap and stays on after you recheck the seal and connectors.
- The air box needs other parts removed to reach it and you are not sure how they go back.
No shame in it. Knowing when to stop is part of the skill. Find a mechanic near you on MechanicRank.
Questions People Ask
How often should I change the engine air filter?
Your owner's manual has the real interval. Many cars fall somewhere around every 15,000 to 30,000 miles, and sooner if you drive on dirt or dusty roads. When in doubt, check it at every oil change.
Will a new air filter improve my gas mileage?
On most modern cars, a dirty filter mainly hurts power and acceleration more than mileage. It is still worth changing on schedule.
Can I clean and reuse my air filter?
Standard paper filters are made to be replaced, not washed. Some aftermarket filters are washable. Follow the maker's directions for those.
What is the difference between the cabin and engine air filter?
The engine filter cleans air going into the engine and sits under the hood. The cabin filter cleans air coming out of your vents and usually sits behind the glove box.