The exhaust system directs hot, used exhaust fumes out and away from the engine bay, and often muffle the sound of the engine while doing so. The exhaust system can also contain sensors which the ECU can use to improve the engine's performance.

Not every exhaust system uses the same parts; many race cars don't use mufflers, many older vehicles aren't equipped with oxygen sensors, and the ones that do have those sensors don't always have them in the same location. Because of this, the start-to-finish flow of exhaust gasses can't be described for every vehicle with just one description, but you can find descriptions of each component and their purposes below:

Exhaust Components: