Exhaust system: What are its main components?

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The car's exhaust system removes the exhaust gases produced during combustion from the engine and ensures that they do not enter the cabin. This system consists of several car parts; its other task is reducing noise and emissions released into the air. Therefore it is designed precisely for a specific type of engine.

This article will shed light on the exhaust system's composition and briefly summarize each component's purpose.


Exhaust pipes

Exhaust pipes

The exhaust pipe takes gases from the cylinder head straight to the exhaust pipe. The exhaust ducts are composed of a group of pipes joined at the end into a single pipe.

The speed of gas movement is affected by the length and shape of the exhaust pipes. If the pipes are short, the gases lose speed after leaving the cylinder head. However, if the downpipes are long, the speed is maintained, and the gases reach the exhaust pipe more quickly.

Catalytic converter

Catalytic converter

The catalytic converter reduces the number of harmful substances in the exhaust gases by creating a chemical reaction that reduces the amount of CO2 and NOx, i.e., carbon dioxide and nitrogen oxide.

Lambda probe

Lambda probe

A lambda probe is a sensor located in front of the catalytic converter or directly in it. Some cars are equipped with two lambda probes. The first is located in front of the catalytic converter and evaluates the amount of oxygen in the exhaust gases.

The engine control unit can adjust the fuel dosage based on that information. The second lambda probe is located inside or behind the catalytic converter and checks that it is working properly.

Exhaust muffler

It comprises several partitions through which perforated pipes wrapped in noise-absorbing materials lead.

Exhaust tip

A pipe is located at the back of the car to divert the exhaust gases outside the car.


Many car enthusiasts increase their car's performance by modifying the exhaust part with tuned pipes, throwing out the catalytic converter, gutting the muffler, and other ways. However, these modifications do not always increase the car's performance, especially if done by amateurs.

In addition, these modifications significantly increase the noise, which can be a problem during the technical inspection. When being pulled over by the police, you may have to pay a hefty price for these mods.