How Does a 4-Stroke Engine Work?

Today’s automobile uses a 4-stroke cycle engine. Whether you’re renting a car or want general information on this type of engine, below is a brief working explanation of a 4-stroke engine:

What Exactly is a 4-Stroke Engine?

A 4-stroke engine is a type of engine which converts the fuel’s chemical energy into mechanical energy with heat as an in-efficient residue. The main reason it’s been called four strokes is because of its number of strokes at one time. 

This type of engine uses three cycles until it intakes the fuel again. It’s widely used in automobiles and generators for fuel efficiency and to reduce pollution emissions.

A 4 stroke engine works in the four cycles. Below are these cycles:

Fuel Intake Stroke

In the first stroke, 1/2 pistons move from the top to the bottom in the engine’s bore. When this happens, the intake valve opens, and the sprinkler sprinkles the fuel in the bore. The downward motion of the piston creates a vacuum in the bore that expands the molecules of the fuel and turns it from liquid to gas.

Compression Stroke

In the second stroke, the piston moves upward back to the top of the bore. However, the vacuum generated in the 1st stroke compresses the fuel gas when the piston moves upward. 

According to thermodynamics, when a gas is compressed, its temperature drastically increases. Due to this nature, the fuel gas in the bore gets heated up enough that it turns into a spark. 

It happens due to the air, fuel, and sudden increase in the volume of the fuel gas, making a small explosion in the bore.

Power Stroke

When the fuel burns and explodes in the bore, it creates a lot of energy. This energy has to convert into some other form. In that case, the energy is converted into mechanical energy. 

The energy generated by the explosion in the bore makes the piston go down. In simple language, chemical energy is converted into mechanical energy.

Exhaust stroke

In the last stroke, the piston moves upward again due to the momentum generated in the piston. The power stroke adds momentum to the piston that transfers it to the crankshaft. In this stroke, the intake valve is closed, the exhaust valve is open, and the exhaust that comes from the vehicle’s silencer is the 4th stroke of the piston.

Important Components

The 4 stroke engine comprises hundreds of components. However, below we’ve mentioned the 3 most essential components of this engine:


A piston is a circular rectangle moving disk enclosed in a bore of the engine. It converts the fuel energy into mechanical energy that drives the crankshaft and hence the vehicle.


The valves in the engine are components that restrict the internal combustion in the piston as per the needs for efficiency. The number of valves is dependent on the engine, but usually, there are four valves in one piston, of which 2 are fuel intake valves and 2 are exhaust valves.


A crankshaft is an important component in the four-stroke engine that drives the whole car and makes the pistons stable. It works as a counterbalance between all the pistons so that the engine doesn’t vibrate when pistons are going up and down in the bore.

You May Also Like To Rent A Car

  • 1700 AED / Month
  • 110 AED / Day
11% OFF
  • 2600 AED / Month 2300 AED / Month
  • 170 AED / Day 150 AED / Day
9% OFF
  • 3200 AED / Month 2900 AED / Month
  • 200 AED / Day 160 AED / Day

You May Also Like


Rent Nissan Micra from Our Car Rental Mall of Emirates, Dubai


Places to visit in Dubai with car rental Dubai


How to save money while renting a car from Dubai Airport

Request Call
Chat on WhatsApp Inquire 80022799