Which part of the engine helps expel exhaust gases?

The exhaust manifold is a crucial component of the engine that is specifically designed to collect and channel exhaust gases from the engine's cylinders and direct them into the exhaust system. After combustion occurs in the cylinders, the exhaust gases are produced as a byproduct. The exhaust manifold captures these gases at the cylinder head, where they exit the engine, and allows them to flow out through the exhaust system, which typically includes additional components such as the catalytic converter and muffler.

The design of the exhaust manifold is critical for optimizing engine performance, as it must effectively manage the flow of exhaust gases to minimize back pressure and enhance overall engine efficiency. Proper function of the exhaust manifold is necessary to ensure that harmful emissions are properly routed and treated before they are expelled into the atmosphere. This contrasts with components like the intake manifold, which is responsible for delivering air and fuel to the engine's cylinders, and the piston rings, which seal the combustion chamber and control oil consumption. The fuel rail delivers fuel to the injectors but does not play a role in exhaust gas expulsion.