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How car engine works

How Car engine Works..?

How car engine works
How car engine works

We all get that mechanical engineer feel when our car suddenly breaks down and when we open the car hood and start exploring. When it is all set we simply start the car which is as easy as turning the key and ride. But have any of you ever wondered or bothered to know what actually happens under the car hood?

Car Engine

A car engine may look like a jumble of metal with n number of tubes and wires running over it. But the process that takes place inside the engine is simple and I will tell you how is that.

Our body and car are much similar. Whenever our body needs fuel we feed it with food. Similarly whenever a car needs fuel, we feed it gasoline or diesel. A car converts the gasoline or diesel into motion just like how we convert food into energy.

Car engines are Internal Combustion (IC) Engines, which means that combustion (burning) takes place internally. There is two and four stroke combustion cycle, but the one that car engines use is the four stroke combustion cycle.


  • Intake stroke
  • Compression stroke
  • Combustion/Power stroke
  • Exhaust stroke

A stroke is the distance the piston moves up and down inside the cylinder.


This is the first stroke that happens in the engine. Initially the piston is at the top position, the intake valve opens and the fuel (gasoline/diesel) along with the air enters into the cylinder. When this happens the piston is pushed down. Once the air and fuel enters into the cylinder, the intake valve closes.


As the compression cycle starts, the piston moves upward and compresses the air-fuel mixture. Compression helps in making the explosion more powerful.


As the air-fuel mixture compresses and creates high pressure, the spark plug creates a spark that explodes the air-fuel mixture. The explosion creates a powerful force that drives the piston downwards.


This is last part of the cycle. When the piston moves downwards, the exhaust valve opens and the exhaust gas leaves the cylinder.  The exhaust gases then passes through the catalytic converter and then through the muffler (silencer).

The catalytic converter converts three harmful components in the exhaust gas into harmless components and the muffler does a great job in reducing the noise level.

Now all the strokes are over and the engine is ready for the next cycle. So the engine intakes another charge of air and fuel.

As I said, the phenomenon in a car engine is four step simple process. Pagani Huayra, Lamborghini Reventon, Aston Martin One, BMW, Ferrari La Ferrari or Porsche 918 Spyder? Which is your favorite? My dream wheel is the spectacular Lamborghini Reventon.