How does a combustion engine work?


A combustion engine, also known as an internal combustion engine, operates by burning a mixture of fuel and air within a confined space. Here's a simplified overview of how it works:

Air Intake

The engine draws in air through an intake valve. Air is necessary for combustion because it provides oxygen.


The engine’s pistons move upwards in the compression stroke, compressing the air-fuel mixture within the cylinder.


The explosion generates a high-pressure, rapidly expanding gas that forces the piston down within the cylinder. This downward motion is what ultimately drives the vehicle’s wheels through a connected crankshaft.


The engine cycles through these processes many times per second, generating continuous power to propel the vehicle.


A precise amount of fuel is injected into the air intake, creating a combustible air-fuel mixture. In gasoline engines, this is typically done via fuel injectors, while diesel engines use direct injection.


When the air-fuel mixture is compressed, a spark plug (in gasoline engines) or the heat of compression (in diesel engines) ignites it, causing a controlled explosion.


After the power stroke, the exhaust valve opens, and the remaining exhaust gases are expelled from the cylinder.