8 Symptoms of a Dirty Air Filter (and Replacement Cost)

Every car engine has a combustion chamber, and this chamber needs air to generate enough energy to run your car engine. However, the air circulating in the engine must be clean and unpolluted.

This is where an air filter is essential as it protects your engine from contaminated air.

Because of its central function, a vehicle’s air filter is less likely to become dirty over time. Air filters negatively affect or fail your car’s performance due to restricted air flow to the engine.

As a car owner, you should know the symptoms of a dirty air filter to ensure your engine remains free of debris. Read on to learn more about air filters and how to replace a faulty air filter.

What does an engine air filter do?

An air filter prevents dirt, debris, contaminants, and road bugs from reaching the engine and ensures there is an adequate supply of air to the engine’s combustion chamber.

Once an air filter becomes too clogged and no longer works, it can reduce the car’s performance and even damage the engine.

To avoid this, automotive experts recommend replacing filters every 12,000 miles or 12 months, but be sure to check your owner’s manual for details on the vehicle’s air filter replacement schedules.

One of the best and easiest upgrades you can make to your vehicle is to purchase a reusable air filter like a K&N filter. You’ll pay more upfront, but it will last the life of the vehicle since you only need to clean it and re-oil it. As a bonus, you can squeeze out a little more power.

See also: Clogged fuel filter symptoms

Signs of a clogged air filter

As stated above, a faulty air filter can significantly affect the performance of your car’s engine. But what are the symptoms of a clogged air filter? Here are eight telltale signs of a dirty air filter:

#1 – Abnormal engine noise

When your car is idling, you should hear the typical smooth-running hum that you are used to. If your engine air filter is clogged, the correct amount of airflow will not be able to reach the combustion chamber, and you may hear a clicking, crackling, or coughing noise.

You may even hear a slight hiss if the airflow is restricted due to excessive buildup on the filter screen. This should not be confused with a sibilant sound when accelerating. In this case, it is only the engine that draws in outside air through the filter.

In addition to strange noises, your vehicle may also vibrate excessively as a lack of air affects the air-fuel ratio.

#2 – Lack of power

Since there is not enough air in the engine, it will not run as efficiently as it should. Poor acceleration is a telltale sign of a dirty air filter.

If you feel that your car seems slower and a little sluggish, checking the condition of your air filter should be your first step (always check the cheapest and easiest reason when diagnosing your air filter). ANY automotive problem).

#3 – Your check engine light comes on

Service lights are another indicator of a bad air filter. As your engine burns, your car naturally produces carbon deposits as a byproduct.

A clogged air filter restricts airflow to the engine, resulting in insufficient air supply and excessive fuel consumption. This causes excessive carbon deposits and will eventually trigger the check engine light.

To confirm, you will need to scan your vehicle with a diagnostic tool, as a check engine light can mean hundreds of different things.

#4 – Visually dark and dirty air filter

A clean air filter is usually white or off-white in color. If the K&N filter is reusable it will be more of a plum color.

As dirt and external debris continue to accumulate on the surface of your filters, their color will gradually begin to deteriorate. You can manually check the air filter to determine if it needs to be replaced.

Often, all you need to do is undo a few clips on the air freshener bottle or cap to inspect it. If you’re still not sure if you need to change it, take out the filter and look at it during the day or with a flashlight to see how clogged it is. Please note that the inner layers of filter paper inside the air filter should not have any visible debris or dust, even in bright light.

Be sure to have your mechanic check the air filter when you hand in your car for service and follow the manufacturer’s instructions for replacing the air filter. The car dealer’s service area will automatically check the filter for you.

Related: Why is there oil in my air filter?

#5 – Reduced Fuel Economy

A car engine uses gasoline and air to start and generate power. When the air supply is insufficient, your car’s engine makes up for the deficiency with too much fuel (this is called “getting rich”). This condition increases fuel consumption.

This is why a drop in your MPG is a clear sign that you may need to replace your air filter.

#6 – Engine Misfire

A dirty filter reduces the air supply to your car’s engine and leaves unburned fuel. This fuel forms the soot residue on the tip of the spark plug.

As a result, the spark plug cannot provide an adequate spark to ignite the air-fuel mixture and subsequently, your car engine misfires or fails to idle, especially when you are accelerating.

#7 – Black smoke, soot or flames coming from the exhaust

As mentioned above, an insufficient amount of air in the engine can lead to incomplete combustion of fuel in the combustion chamber.

Unburned fuel exits the engine through the exhaust, leaving dark gray or black smoke. In rare cases, you may even notice flames coming out of your exhaust pipe. These flames cause unburned fuel to burn due to heat in the exhaust system.

#8 – Gasoline smell when starting

A strong gasoline smell is another sign of a very dirty air filter.

With insufficient air supply, unburned fuel exits the engine and may not produce smoke or flames in the process. Instead, this fuel will emit a distinctive gasoline smell, a reliable indicator of a faulty air filter.

Engine Air Filter Replacement Cost

As with other car maintenance services, air filter replacement costs depend on the car model and where you look for help. One of the easiest DIY jobs you can do on your vehicle is replacing the air filter, so 95% of people should be able to change it themselves.

On average, expect to pay between $10 and $25 for a standard paper air filter at an auto parts store. You can save a few dollars by shopping at Walmart or Amazon.

A reusable air filter will cost you on average between $45 and $80, depending on the vehicle. After the first year, you will also need a cleaning kit for your reusable K&N filter. Fortunately, the cleaning kit is not cheap and will last you several cleanings.

If you want to have your filter replaced by a professional, they will charge you around $20-30 for their time in addition to the cost of the filter (which will also have a surcharge). With parts and labor, add about $50 to $90 depending on your vehicle and where you’re going.

Many mechanics or dealerships will allow you to purchase the filter yourself and take it in to have it installed. This way you will always save money without getting your hands dirty.

Can an air filter be cleaned or washed?

Choosing to clean or not clean an air filter depends on the type of air filter you use in your car.

There are three types of air filters:

• Disposable
• Reusable (gauze)
• moss (rare)

You can’t clean a disposable air filter, so replacement is the only option. However, you can clean the reusable filters and foam, but only with specific applications, and you should dry them before replacing them.

Putting a wet filter back into the car engine will have a negative effect on the car engine.

See also: How to clean the cabin air filter

What happens if you drive your car without an air filter?

Running your car without an air filter can introduce dirt, leaves, debris, bugs, and a host of other contaminants into the air.

These harmful elements cause significant damage to the internal parts of your car’s engine, such as pistons, valves, and cylinders. Additionally, your engine’s fuel and oil consumption will increase significantly, which could lead to engine failure.

Therefore, for safe and optimal performance of your engine, be sure to address dirty air filter symptoms immediately and always have a clean air filter in place.