What Does An Intake Do?

Intakes are vital automobile components that work to bring oxygen – a key ingredient in an internal combustion reaction – into the engine’s combustion chamber to modulate how much oxygen mixes with burning fuel.

car intake

It sounds like a complex component. In reality, intakes are relatively easy to understand once you understand the greater intake system.

Let’s examine what an intake does so you can have a better appreciation for how your engine works the next time you step on the gas.

Car Air Intake Systems

In an internal combustion engine, a few ingredients are necessary to produce the explosive energy required to turn your car’s wheels. Those ingredients are fuel, a spark, and oxygen. Fortunately, our atmosphere is primarily comprised of oxygen and nitrogen. All we have to do to start a chain reaction is ensure that air and fuel are mixed before being exposed to a spark.

Car air intake systems provide this air and deliver it to your car’s engine. When working properly, air intake systems allow for continuous airflow into your engine, which offers greater, more consistent power and improved mileage for the vehicle.

What Exactly Do Air Intake Systems Do?

In the simplest terms, air intake systems bring air from outside the vehicle into your engine’s intake manifold, where it is then mixed with fuel from your gas tank. The air/fuel mixture is ignited and sent through to your car's engine cylinders to drive the explosive action that is translated to physical energy, eventually turning your car's wheels thanks to the transmission.

Without air intake systems, vehicles would not be able to rely on a continual internal combustion reaction. Any produced motion would be sporadic and unusable.

Main Parts Of Common Intake Systems

There are three primary components used in functioning air intake systems. Let’s break them down one by one, so you can better understand how this essential system works when you turn your vehicle on and engage the accelerator.

Air Filter

The air filter is the first primary component of this system. It is a metallic or plastic box that contains a dedicated filtration screen and is typically located ahead of your car’s throttle valve assembly or intake manifold.

You can locate it by popping your car’s hood and finding a boxy compartment near the throttle valve assembly. It looks very similar to commercial filters for vacuum cleaners and similar appliances.

Air filters help the system by filtering dirt and other particles from the air. In doing so, the filters prevent contaminants from clogging up the air intake system and potentially damaging your car’s engine. Purer oxygen also results in better engine performance since the resulting combustion reaction is more efficient.

Mass Flow Sensor

Your car’s air intake system also uses a mass flow sensor to detect how much air enters the engine. The internal combustion reaction must be adequately balanced to produce the correct amount of energy for your current driving needs.

Modern automotive engines use two types of mass airflow sensors: vane meters and hot wires.

Vane meters use flaps that are pushed by incoming air from the filter tube. As more air comes in, the flap is pushed back further. The flap movement is measured by the meter, which estimates how much air is flowing into the engine at one time.

The hot wire sensor type operates similarly but uses a collection of wires that are strong across the incoming air stream. The wires’ electrical resistance increases as the temperature increases, triggering a current reaction and allowing for a measurement of approximate airspeed and mass.

Throttle Body

Lastly, the intake system’s throttle body controls the air flowing past the sensor mentioned above. Throttle bodies are components characterized by hollow or bored housings that hold a throttle plate rotating on a shaft.

As your accelerator is depressed, your engine’s throttle plate opens and allows air into the engine. When you release your accelerator, the throttle plate closes and prevents airflow from reaching the combustion chamber, stopping the chain reaction. In this way, the throttle body controls the combustion rate and, therefore, your vehicle’s speed.

Cold Air Intake Systems

Cold air intake systems are advanced versions of the above basic system. As their name suggests, cold air intakes bring cooler air into your engine and combustion chamber. In doing so, cold air intakes boost engine power and efficiency.

That’s because colder air has a higher oxygen density. More oxygen is included in a given volume of cold air than a given volume of warm or hot air. Therefore, the resulting combustion reaction is more effective, producing more engine power and greater mileage.

Cold air intakes operate by replacing the regular airbox with a metallic or plastic tube that leads into a conical air filter. Heat shields are included to protect the air filter from the surrounding engine components, which can get quite hot after the engine has been running for even a short while.

In this way, the cold air intake keeps the outside air cool relative to the engine environment, allowing for better combustion reactions.


Air intake systems are vital parts of your car’s engine. Without air intake systems, your engine might not run at all, and it certainly wouldn’t be controllable to the same degree. Air intake systems allow drivers to control their vehicles’ speed by modulating the rate of internal combustion reactions, thus keeping your car cruising along on the road.