8 Symptoms of a Dirty Air Filter and Replacement Cost

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dirty air filter

Are you a car owner who’s been putting off getting your dirty air filter replaced? Well, you’re not alone. Many car owners put it off because they think it will be expensive or complicated. But the truth is, it’s neither of those things.

In fact, changing your filter is a quick and easy way to improve your car’s performance and gas mileage. If a car’s engine is its heart, its air intake is its lungs. Whenever we inhale air, we provide vital oxygen to our whole body.

Just like people need air to survive, our automobiles do as well—but what goes when a clogged air filter prevents this vital oxygen from entering? Every internal combustion engine requires air to operate, and a clogged air filter may cause a car to choke.

This may result in significant complications down the line. Fortunately, dirty air filter signs and symptoms are simple to recognize if you understand what to search for. So what are you waiting for? Read on for more information about dirty air filters and how to deal with them.

Dirty Air Filter Symptoms

  • Visible Dirt
  • Decreased Fuel Economy
  • Unusual Noise
  • Reduced Horsepower
  • Black Smoke Or Flames
  • Fuel Odor
  • Misfiring Engine
  • Check Engine Light

Functions Of Air Filter

Automobile air filters cleanse the air within a vehicle, ensuring that passengers inhale safe, clean oxygen. An automobile air filter is classified into two forms: panel style, which is found on most fuel-injected automobiles, and radial style, which is often found on carbureted cars.

An automobile air filter is housed in a dark plastic or metal shell and is usually located at the engine’s side or center-top. The filter captures dirt particles that may wreak havoc on your engine’s cylinders, sidewall, pistons, and rings. Regularly replacing your car’s filters could substantially influence the engine’s lifespan and efficiency.

Changing your air filter once or twice annually, or around every 15,000 miles, is a decent rule of thumb. Changing a clogged air filter benefits your car engine: it improves fuel efficiency by up to 10%, resulting in equivalent fuel savings of up to 15% per gallon.

Air filter replacements would be required more often in dusty and dirty driving environments. It’s critical to prevent installing the incorrect type of air filter in your vehicle.

Currently, automobile owners use Nanotechnology-based air filters to enhance the condition of their cabin air. These air filters feature layers of charcoal that absorb smells.

These filters enable mechanical filtration, wherein the filter’s fiber composition with holes of a specific size traps particles bigger than the pores. Almost 80% of automobiles sold globally are equipped with a nanotechnology-based air filter.

Dirty Air Filter Symptoms

Understanding some of the obvious indicators of a clogged or dirty engine air filter will help you avoid postponing replacement for an extended period. Below are various indicators that it’s time to replace your car’s air filter.

Visible Dirt

You can always do a visual inspection if you recognize where your air filter is (or check your owner’s handbook). Your air filter must clearly reveal its color if it’s clean. If dust and grime gather on it for an extended time, your air filter will darken, and the dust will become visible.

Whenever your air filter appears dirty, or it begins to seem black or gray and dirty, it’s probably time for a brand new air filter.

Decreased Fuel Economy

A reduced fuel economy is a frequent indication of a problem. While your engine air filter helps with gas mileage, a dirty filter might result in decreased oxygen flow. A car should adjust for this by using more fuel than usual. A clean air filter maintains the air supply flowing and keeps fuel efficiency on track.

Unusual Noise

When your automobile is idling, its engine must emit its unique humming. A dirty engine air filter limits the quantity of air supply of air supply delivered to the engine’s combustion chamber. The combustion chamber might sputter, pop, or make strange engine noises in response. Additionally, strange noises may be followed by vibrating or trembling.

Reduced Horsepower

Whenever your automobile doesn’t respond adequately or if you notice jerking actions when you step on the gas pedal, this could mean that your engine isn’t getting all the air it requires to operate properly. Since it enhances airflow, replacing your air filter can enhance horsepower and acceleration by up to 11%.

Black Smoke Or Flames

Insufficient air intake entering your engine might result in inefficient fuel combustion inside the combustion chamber. Unburned fuel is expelled from the engine via the exhaust, resulting in black sooty smoke. Occasionally, you might witness flames spewing from your exhaust.

Those flames are caused by unburned fuel igniting because of the heat generated inside your exhaust system.

Fuel Odor

Whenever excess unburnt fuel exits from your exhaust pipe, it emits that distinct odor that alerts you to the fact that something is wrong. While a stench may also signal a gas tank leakage, you might verify your concerns about exhaust leaking by looking for black smoke.

Misfiring Engine

A clogged engine air filter reduces the quantity of air that the engine receives. This could result in an upsurge in unburned fuel that forms soot residue. Soot may accumulate on the tip of your spark plugs, rendering them incapable of delivering a proper spark. As a result, the vehicle may jolt, crank, and, in some instances, the engine could misfire.

Check Engine Light

The check engine light might illuminate for various causes; it might be as straightforward as a loose fuel cap or indicate a more serious issue. Among those explanations might be that your engine is not receiving enough air, resulting in carbon buildup in your engine, which activates the dashboard’s bright light.

Once you bring your vehicle to a technician, they will perform a brief scan to determine what is creating the issue and inform you whether it’s a dirty air filter issue.

Benefits Of Replacing Your Bad Air Filter

While your air filter may not sound like a critical component to inspect and replace regularly, they are essential for preserving your vehicle’s performance. The filter keeps microscopic particles out of your engine, preventing possibly costly damage. However, as stated below, this is not the only benefit.

Reduced Emissions

A blocked or dirty air filter could restrict the air flowing to your engine, altering your vehicle’s air/fuel mixture. This imbalance might contaminate your spark plugs, leading your engine to misfire or idle irregularly; it can also cause engine carbon deposits.

The imbalance significantly affects your vehicle’s exhaust emissions; more dark smoke coming out of your exhaust pipe means adding to environmental pollution.

Increased Gas Mileage and Better Performance

A clean air filter enhances the amount and quality of air reaching your engine and thus enhances your engine performance.

A dirty air filter won’t allow the same quantity of air to penetrate your engine as a cleaner one could. Research has revealed that fuel efficiency can be increased by 14% with a fresh and new air filter.

Prolongs Engine Life

Regularly replacing your dirty air filter is a low-cost approach to prolong the lifespan of your engine. Dirt and dust particles could cause harm to your engine’s internal components, such as cylinders and pistons.

How Often to Replace Engine Air Filter

Although manufacturers suggest different intervals for air filter replacement, it’s time to get it checked whenever you detect any of those indicators above of a dirty or bad air filter.

You can inspect your air filter yourself or let a professional do so. To remove your filter, first, consult your owner’s handbook for the location of your filter and then follow the step-by-step instructions for uninstalling the filter.

Unless your engine air filter is spotless or hardly filthy, it is alright to leave it in, but it’s always up to you. A slight coating of dirt could be removed by tapping the surface to dislodge any loose dirt material. The filter should be replaced if completely covered with dust and other pollutants.

Engine Air Filter Replacement Cost

The cost of replacing a bad air filter might differ based on your car’s year and make & model. An air filter is typically inexpensive, so you might anticipate spending as little as $10 to somewhere about $70.

If you get a professional to replace it, the projected cost might climb up to a spectrum of $60 to $170 due to increased labor expenses.

The cost might also fluctuate based on the kind of filter you choose. Some auto shops could ask more or less for services based on your location, but you can still DIY and spare an additional dollar.


All of the components of an automobile operate in unison. Once one component fails, a domino effect of problems develops from one mechanism to another.

A faulty filter might result in various problems, including hazardous emissions, malfunctioning spark plugs, wasted fuel, and engine damage. That’s why it is prudent to monitor components for some possible damages.

Don’t be alarmed if you discover signs of a dirty air filter. It’s a simple and affordable remedy. As long as your engine is breathing clean air and managed, you can avoid many of these readily preventable problems and prolong the lifespan of your car.


What happens if you don’t clean your car’s air filter?

Whenever the filter is dirty and becomes clogged, the engine is forced to operate harder and gets less efficient, resulting in decreased horsepower and acceleration, increased fuel consumption, poor engine performance, and increased engine stress.

Will a dirty air filter cause a car to run rich?

When your car’s air filter is clogged, you might notice decreased gas economy. With such a filthy air filter, your car will effectively run rich, burning an excessive quantity of fuel and inadequate air supply. A clogged air filter could reduce a car’s gas economy by up to 10% in certain situations.

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