Time for a New Car Air Filter? Visit Our BMW Service Center

Mar 11, 2022

Combustion requires thousands of gallons of clean air, and all of this air passes through the car air filter. This filter traps dust and dirt that would otherwise contaminate the engine. In time the filter will get jammed with dirt. As your BMW dealer in Fayetteville, NC, we can fit a new one for you. These are signs it’s time to change the filter.

Check Engine Light Comes On

The check engine light covers a myriad of problems in the engine. Sensors are attached to all the important components to monitor them. If a sensor detects unusual behavior by a particular component, the check engine light will illuminate. One of the reasons it can light up is a build-up of carbon in the engine.

For combustion to happen, air, fuel, and a spark are needed. The air comes in from the air filter, the fuel enters when you step on the pedal, and the spark plugs provide the spark. If your air filter is blocked, the process will be more difficult. The reduced amount of air means that combustion will be fuel-rich. When this mixture burns, it leaves behind deposits of unburnt carbon. This carbon build-up will trigger the light.

Misfiring From the Engine

For efficient combustion, you need a ratio of 14 to 1 air to fuel. A dirty air filter severely restricts airflow. The limited amount of air available means that much of the fuel used in the process won’t be able to burn. As we’ve seen, the combustion chamber becomes fuel-rich due to the lack of clean air. To spark effectively, the spark plugs need air.

The lack of air from the blocked filter makes misfiring far more likely. Misfiring is incomplete combustion in one or more of your car’s cylinders. Fuel without air doesn’t burn easily, and it also coats the spark plugs with sticky black carbon. The lower the level of air in the engine, the greater the chance for misfiring.

Air Filter Is Dirty

Some car problems are easy to see, others are more difficult. A dirty air filter is an easy problem to check. Your car manual shows the location of the air filter box. If you open the hood and find the box, you’ll be able to see the current state of your filter. Air filters are white or cream, but as they fill up with dirt they change to a dark brown or black.

The dirtier the air filter, the less air that’s entering your engine. Air filters are very easy to replace, and we always have stock available. Once the filter is replaced, your engine performance will drastically improve.

A dirty filter reduces your car’s power, can damage engine parts, and will also cost you more at the pump. The inefficient combustion caused by a dirty filter forces your engine to use more fuel. Call our service department today at Valley Auto World BMW and we’ll fix that filter problem.