When a driver turns a key in the ignition:

●      The car battery powers up sending

●      Power to the starter motor, which

●      Turns the crankshaft, which

●      Gets the pistons moving

●      With the pistons moving the engine fires up and ticks over

●      A fan draws air into the engine via an air filter

●      The air filter removes dirt and grit from the air

●      The cleaned air is drawn into a chamber where fuel (petrol or diesel) is added

●      This fuel-air mix (a vaporised gas) is stored in the chamber

●      The driver presses the accelerator pedal

●      The throttle valve is opened

●      The gas-air mix passes through an intake manifold and is distributed, through intake valves, into the cylinders. The camshaft controls the opening and closing of the valves.

●      The distributor makes the spark plugs spark, which ignites the fuel-air mix. The resulting explosion forces a piston to move down which in turn causes the crankshaft to rotate.