Exhaust System- How Do They Work?

When your car is running, there are thousands of small explosions inside your engine every minute. Each one produces power by pushing against the engine’s pistons. But the explosions also produce leftover gases. 

They’re made up of potentially dangerous chemicals. These gases need to be routed away from the engine compartment so they don’t get into the cabin, and then into your lungs. That’s the basic job of a car’s exhaust system. There are various performance parts in your car that you should look at:


For most cars, it all starts with the exhaust manifold. This is made of metal, usually cast iron, and connects the engine to the rest of the exhaust system. 

On one side of the manifold are individual tubes that connect to each of the engine cylinders. They merge together in the manifold and come out of the other side in a single tube. 


If you’re a hot-rod enthusiast, you may opt for “headers” instead of a traditional exhaust manifold. Headers also collect the exhaust gases from the different cylinders into one tube, but the individual tubes for headers are much longer. This reduces the pressure needed to force the exhaust gases through the system, increasing performance.


An oxygen sensor is a part of the exhaust system that helps fine-tune the intake process. Often located in the exhaust manifold, the sensor measures how much oxygen is in the waste gases. In a perfect world, there wouldn’t be any. 

The engine would use exactly the right amount of oxygen needed to completely burn the fuel, and none of either would be leftover. With a modern fuel-injected car, the ECU (engine control unit) analyzes the oxygen reading from the exhaust sensor.