How does a Car’s Exhaust System Work?



Together with the engine and suspensions, the exhaust system is one of the key elements that determine a vehicle’s overall performance. To understand more about its function and the maintenance required to keep it going, we’ve here at Roberts AIPMC have come up with this post explaining how exhaust systems work.


What are its primary functions?

Exhaust systems not only favor the environment’s cleanliness, but they also contribute to the safety of the driver and its passengers in the way it funnels potentially harmful gases away from the engine compartment. Additionally, engine noise is also reduced while exhaust emissions are minimized.

This is with its main role of taking the gases produced by your engine away from the engine compartment. It also lessens the noise of your engine and reduces the exhaust emissions.

Car Exhaust System

What is it composed of?

The exhaust system is composed of an exhaust manifold, catalytic converter, resonator and a muffler, which is where the gases are silently released. When the engine is working, the resulting exhaust gases are carried to the exhaust manifold through the exhaust vault. The pipes from which the gases will then pass through help in the cooling of the exhaust gas, but it is in the catalytic converter where they undergo the purification process.

Before entering the catalytic converter, the gases – a mixture of carbon monoxide, unburned hydrocarbons and nitrogen oxides – are increasingly harmful to the environment due to partial combustion. This fact establishes the importance of having fully functional exhaust system for all vehicles.


How does the purification process work?

Inside the converter are two ceramic blocks that act as catalysts: Platinum and Rhodium. The toxic gas in the first ceramic block are heated up, causing the catalysts to react. Here, oxides of nitrogen are separated and reformed into nitrogen and oxygen. Meanwhile in the micro ducts of the second ceramic block, carbon monoxide reacts with oxygen to form carbon dioxide.

Unburned hydrocarbons also react with oxygen to create water and carbon dioxide. With the catalyst converter, the exhaust gas is transformed and becomes less toxic.. The gases that come out of the converter are then a mixture of carbon dioxide, nitrogen and water vapors.


What’s the muffler for again?

Consisted of different-sized chambers, the muffler cancels any noise caused by the exhaust system’s process, thus resulting in a smoother ride. Within the muffler’s first chamber are drilled holes where sound waves move back and forth before coming out. The resulting friction eliminates the sound waves, which marks the time for the gas to enter the resonator.

Opposite sound waves of similar frequencies are generated when they hit and bounce from the wall of the resonator. This allows the cancellation of sound waves to go to the next chamber to further minimize the noise by friction. The exhaust system’s job then ends as the significantly less harmful gas exits the tail pipe.

Our experts understand the function and purpose of exhaust systems all too well, which is why the ROBERTS Soundex Mufflers are amongst the best of its kind here in the Philippines.