Car Engine Air Filter: What Is It & How To Replace One
- Function of Engine Air Filter
- Symptoms of a Clogged Engine Air Filter
- How to Change an Engine Air Filter
- Engine Air Filter Replacement Cost
- FAQs
A car engine air filter or car air filter is designed to prevent dust and debris from entering the engine. Over time, the air filter becomes clogged and blocks the optimal supply of air. This results in issues such as reduced performance, overconsumption, excessive emission and engine malfunction. In this guide, we will discuss a car engine air filter, how it works and how to replace it.
What Does an Air Filter Do in a Car?

Before changing your car’s air filter, you need to understand how it works. Air filters clean the air that draws in by the car’s engine and mixes with the fuel to form the correct compression ratio. Since it is essential to prevent impurities from entering the engine’s combustion chamber, there is always an intake air filter located just before the intake manifold. Most cars use special paper filters with an accordion structure which greatly increases the filtering area.
How Often Do You Need to Change A Car’s Air Filter?
Debris and dirt deposit on the filter, reducing the amount of air that passes over time. A lot of factors impact how soon you will need to replace the filter. Generally, filter manufacturers suggest replacing your car’s engine air filter at least once a year. Automakers suggest replacing them after 20,000 km to 25,000 km.
Also, there are several symptoms that can tell you when to change the car air filter such as sooty spark plug, darken exhaust and reduced fuel economy.
Symptoms of a Clogged or Faulty Engine Air Filter
A clogged air filter can reduce the car’s engine efficiency and should be replaced accordingly. There are various indicators that direct towards a choked air filter. The following is the list of some common signs that require you to change your car’s air filter.

Dirty Air Filter
The first and key indicator is the physical appearance of the air filter itself. The air filter is usually located near the engine components, under the hood. You will need to remove the upper cover which can easily come off by removing its fasteners, clamps or screws.
A dirty air filter will look dark and grimy as opposed to a new white air filter. Dirt accumulation along the filter paper is a prime indicator of a clogged filter and will require a replacement.
Reduced Fuel Economy and Engine Power
A clogged engine air filter means less air is able to pass the chamber for fuel mixing. Lack of air and improper mixing will reduce the energy from the fuel combustion. Hence, your car will be using more fuel.
In addition to low fuel economy, improper combustion will also lead to reduced engine power. The feeling is recognizable if acceleration is not smooth or the engine misfires
Sooty Spark Plug
As a dirty air filter leads to an improper mixture of fuel and air, the irregular combustion deposits carbon soot on the spark plug. This will affect the overall gas mileage and acceleration of the car as the spark plug is unable to ignite properly.
Hence, you will need to clean the spark plugs with gasoline or alcohol to rub off the carbon soot and replace the dirty air filter for proper pre-mixing of fuel and air.
Check Engine Light
The check engine can turn on due to many reasons and air filters might be just one of the reasons. Since it is hard to diagnose the problem on its own, you will need to visit an auto technician to run a scan and detect the problem.
Fuel Smell
A blocked car engine air filter creates a rich fuel mixture due to a lack of air. This leads to fuel odours because of unburned fuel leaving the exhaust system. Apart from a dirty air filter, fuel smell can also be due to leakage in the fuel system or problem with fuel regulators. Nonetheless, you will probably need a visit to a professional for a proper diagnosis.
Darken Exhaust
The rich fuel mixture due to a dirty air filter leaves fuel traces when exiting via the exhaust. This leaves residual unburnt fuel in the form of sooty smoke. Sometimes the leftover fuel particles can even ignite due to hot exhaust temperature, creating small explosions and backfire.
How To Change a Car Engine Air Filter

Here is your step by step guide on how to change a car air filter.
Step 1: Locate the Air Filter
It is fairly easy to locate a car engine air filter. Lift your vehicle’s bonnet and try to look for the engine air filter housing. It is usually a black plastic box located on the side or to the top of the engine.
Step 2: Clean the Outside of the Air Filter
Once you have located the box containing the filter, it is advisable to clean the outside of the box with a brush or compressed air, to prevent engine dirt from being transferred inside when you are changing your car’s air filter.
Step 3: Access and Remove Air Filter
Open the car air filter housing to replace the old car engine filter with the new one. The filter housing can be attached with wing nuts, clips, screws and clamps. Check what type of fasteners are being used and remove them with an appropriate tool.
Lift the cover to which the air inlet pipe is connected and uncover the filter. Carefully lift the filter and remove it. Sometimes the filter gasket is stuck along the edge making it difficult to remove: use a screwdriver to work along the edge until it comes off completely
Step 4: Clean the Air Filter Housing
Before replacing your car’s air filter with a new one, the inside of the filter housing should be thoroughly cleaned to remove any residue. This can be done using a vacuum cleaner or a compressed air gun.
Step 5: Replace the Filter
The new filter can now be placed in the box. Filters are usually marked with an arrow indicating the direction of the airflow. The edge of the filter is surrounded by a gasket which must be secured carefully to the edge of the box. Its correct positioning is essential so that no air other than the one which passes through the filter enters the box.
Step 6: Close the Box
After inserting the filter, put the cover back on the box and secure it in place with the screws or hooks.
Car Engine Air Filter Replacment Cost

The cost of an air filter varies from one car to another; however, the average price of an engine air filter in the UAE is between 150 AED to 250 AED. Whereas, you can save the labour cost by replacing it at home. In case you find difficulty while changing it at home you can take the vehicle to your nearest garage or book them up online. You can easily find a range of auto parts for sale in the UAE at reasonable rates.
FAQs
What if you run a car without an air filter?
Running a car without an air filter will allow contaminants like dust, debris or dirt particles to get sucked into the engine. This can potentially damage the engine components including pistons and cylinder wall and negatively impact the overall engine performance. Environmental conditions like driving along off-road trails can play an important role in expediting the damage.
Can you clean the disposable air filter?
Disposable and reusable air filter, both can be cleaned for reuse. However, reusing disposable air filters is not recommended as the filter can trap small residual particulates into its pore overtime, reducing its effectiveness.
HOW DO I KNOW WHAT SIZE AIR FILTER MY CAR NEEDS?
Consult your car owner’s manual and go through the contents of the ‘Engine Air Filter’ section. You will find information about the right air filter size there.
Now you know how air filter works in cars and how to replace it by following the aforementioned instruction. If you are buying a used car in the UAE, don’t forget to take a test drive and check its engine air filter appears dirty to you. In case you find any issue with the car air filter, replace it with a new one.
This concludes our guide on how to replace car engine air filters. Stay tuned to the UAE leading auto blog to find more car repair and replacement tips.