How exhausts work
Your exhaust has four main functions: to control noise, to direct exhaust fumes away from passengers, to improve the performance of the engine and to improve fuel consumption.
Depending on the make and model of your vehicle and the number of engine valves it has, the layout of your vehicle exhaust system may vary. However, all exhausts work in the similar way in order to remove harmful exhaust gases from the engine which are produced while the engine is running.
All exhausts produce six gases as emissions; of the six, three are toxic (carbon monoxide, nitrogen oxide and nitrogen monoxide). Your exhaust emissions system is the only means of channeling away those noxious fumes.
Exhaust gases are collected from the cylinder head in the engine by an exhaust manifold. The exhaust manifold acts as a funnel, diverting exhaust gases from all cylinders of the engine then releases them through a single opening, often referred to as the front pipe.
These exhaust gases then travel through a catalytic converter which removes harmful elements including carbon monoxide and hydrogen monoxide which are converted into inert gases.
The gases then pass through a silencer or muffler. It's only when you hear a car with a damaged silencer that you realise what a huge difference it makes to reducing noise levels. The silencer on your exhaust contains a deceptively simple set of tubes that are finely tuned to reflect the sound waves produced by the engine so that they cancel each other out.
The silencer will corrode over time and when it eventually develops a hole, no matter how small, the sound waves are no longer forced through the tubes and escape outside – making a lot of noise in the process.
Finally the exhaust fumes exit via the tail pipe at the rear which carries gases away from the vehicle and the passengers inside. All of the components of an exhaust system are connected with a series of clamps, hangers, flanges and gaskets.