How Engine Power Is Created

How Engine Power Is Created

Here at City Garage, we’ve made an effort to educate our customers on the inner-workings of your vehicle. We’ve discussed several different aspects of how an engine converts energy; from what source it receives that energy, and the like. Today, we’re going to discuss how the engine powers itself, and how it creates that power. There are a couple of different aspects to this complicated process. Let’s start with the mixture of petrol and air.


A Combustible Mixture

Air is mixed with petrol, which is just a different name for gasoline, to form a highly combustible mixture in the carburetor. The carburetor is a complicated machine that combines pressure and several different chemicals to form a mixture that is combustible. More on the carburetor can be found on our article about “How the Carburetor Works”


Engine power all starts with the carburetor and the mixture of gasoline and air that forms a combustible combination. This mixture is then drawn into the cylinders through valves, compressed to about an eighth or a ninth of it’s original volume, and then ignited by a sparkplug.  Once the mixture gets going, the rapid expansion of the burning gas creates pressure on the piston that drives it down the cylinder.


Force is created

This pressure is replicated in both of the pistons; one after the other, creating a vacuum of force that pushes the pistons up and down continuously. The cylinder is connected to a connecting rod that is connected to other moving parts. With the rotary movement of the crankshaft, this part of the engine works much like a cyclist pressing his foot to the pedal to turn the chain wheel.


The Firing order is vital to understanding the engine’s smooth operation. The sequence that the sparkplugs ignite the mixture in the cylinders  is known as the firing order. This order has to be carefully calculated and adhered to in the engine’s internal computer. If the spark plugs fired off numerically, the engine would run unevenly and constantly vibrate.


Firing Order

The spark plugs are programmed with the proper order in which to fire, and ignite the mixture. This is why it’s so important to properly replace all spark plugs when replacing or repairing them. If they don’t show up in the same place as they were, your engine could suffer from the consequences. Be sure to check with a trusted professional auto repair mechanic before attempting a spark plug replacement yourself.