Have you been wondering about the secret behind how a car travels from one place to another? Are you a mechanical student, car owner, technician, or driver who is curious about how the internal combustion engine works, its various parts, and what it is? Well, with my decade of experience, I will do my best to explain how it works in this modern age and the technological changes that have been made so far.
Let’s begin!
You should learn about Engine with this detailed guide!
What Is an Internal Combustion Engine?
An automobile engine is known as a “heat engine” or “internal combustion engine.” It burns fuel to generate heat, which produces mechanical energy. For cars and other vehicles, a wide range of propulsion systems are currently or possibly available. The engine is the heart of your car, a complex machine built to convert heat from burning gas into the force that turns the road wheels.
An automobile engine is a positive-displacement internal combustion engine with an intake, compression, combustion, and exhaust stroke. Its main job is to transform energy from fuel into working power. In other words, it produces the power that makes the car move.
The engine is the heart of your car. It is a complex machine built to convert heat from burning gas into the force that turns the road wheels. Different inventions in propulsion systems are widely available for automobiles. These include internal combustion engines fueled by petrol, diesel, propane, or natural gas.
Other options are hybrid vehicles, plug-in hybrids, fuel cell vehicles fueled by hydrogen, and all-electric cars. However, fuel vehicles are not as beneficial due to their limited range and high-cost batteries.
The main purpose of a gasoline automobile engine is to burn gasoline and convert it into motion, which enables the car to move. Aside from electric vehicles, the easiest way to create motion is through an internal combustion engine, which means combustion takes place internally.
Brief History of an Automotive Engine
Early tests of electric motors and steam engines were unsuccessful. The internal combustion (IC) engine dominated the 20th century. As of 2017, gasoline is the fuel of choice for American cars.
Steam and electric engines competed with internal combustion engines in the early 1900s. The idea behind how internal combustion engines operate is that the force of an explosion propels a piston. This explosion is burning the hydrocarbon in the cylinder head of an engine.
At that time, only about one-fourth of the automobiles produced truly qualified as internal combustion. The internal combustion engine emerged as the most widely used vehicle engine throughout the course of the following few years.
Rudolf Diesel developed a brand-new type of internal combustion engine at some point in the 19th century, employing the idea of pumping liquid fuel into air heated only by compression.
This type of motor is the ancestor of the contemporary diesel engine utilized in cars, but more particularly in heavy-duty vehicles like semi-trucks.
Related: Engine Sputtering: Most common causes and how to fix
Major Parts of Internal Combustion Engine
The following are the parts that make up an automobile engine:
- Piston: This is a cylindrical piece of metal that moves up and down inside the cylinder.
- Valves: The valves open and close at the proper time so that air and fuel can enter the combustion chamber and compress to let out exhaust.
- Spark Plug: This is what ignites the air/fuel mixture so that combustion can take place.
- Piston Rings: They prevent the fuel/air mixture and exhaust products from escaping into the sump during compression and combustion. It also prevents the oil in the sump from entering the combustion chamber.
- Crankshaft: This is what converts the piston’s up-and-down motion into circular motion.
- Connecting Rod: This engine part connects the piston to the crankshaft. It rotates at both ends, enabling its angle to change as the piston moves and the crankshaft rotates.
- Sump: It holds the oil that lubricates the engine components.
Diagram Of an IC Engine
Types of Automobile Engine
Internal Combustion Engines (ICEs)
For many years, gasoline- or diesel-powered traditional ICEs have served as the foundation of the automotive industry by providing a balance between performance and efficiency. Their emissions and reliance on fossil fuels raise environmental issues.
Electric Car Engines
Using electricity stored in batteries to power vehicles, electric car engines are at the forefront of sustainable mobility. They are a potential option for reducing the effects of driving on the environment because they offer high efficiency, instant torque, and zero emissions.
Hybrid Engines
These engines combine electric motors and batteries with internal combustion engines, often gasoline-powered ones. Particularly while driving in cities, this hybridization improves fuel economy and lowers pollutants.
The intended purpose, necessary fuel efficiency, environmental impact, and technological improvements all have an impact on the choice of car engine type.
Electric and hybrid engines are becoming more common as the automotive industry transforms toward sustainability and lower emissions, spurring innovation and transforming the future of transportation.
The industry’s dedication to addressing both the necessity of environmental responsibility and the changing desires of consumers is shown in the diversity of car engine types.
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Types of IC Engine by Layout
An engine layout means the number of cylinders in an engine and how they are arranged. There are many kinds of engine layout, but three are popularly used in car engines:
Straight Or Inline Engine Layout
The Straight or Inline engine configuration is the one that is most frequently used. The cylinders are arranged vertically in a line, one behind the other, as the name suggests.
Depending on the number of cylinders, these types of car engines can be installed in the car parallel or perpendicular.
The engine configuration is classified as Straight when it is parallel to the vehicle and as Inline when it is perpendicular to the vehicle. Straight/inline engines are utilized frequently because of how simple and affordable it is to manufacture and install them.
Due to their small size and capacity to fit other automotive components around them, inline engines are often seen in entry-level family vehicles like hatchbacks.
On the other side, straight engines can have more cylinders, which results in more power. Straight engines are found under the hoods of luxury vehicles from brands like BMW and Mercedes.
Flat Engine Layout
A flat engine has its cylinders arranged horizontally, unlike a straight engine. Due to the piston action simulating combatants hitting their gloves before a match, it is also known as the “Boxer engine.”
The boxer engine is well balanced, and by balance we mean that there are fewer vibrations as a result of the force that the pistons produce as they move.
The Flat Engine’s low center of mass is another feature that enhances the car’s handling. Due to their enormous surface area, the cylinders are all evenly cooled by air.
In comparison to straight engines, flat engines are more expensive to produce, and many vehicle manufacturers do not like their wide design.
V-Engine Layout
A common engine design used in almost all high-performance vehicles is the V-engine. When looking at the engine from the front, the cylinder banks, or the space in which the pistons move, are arranged to resemble a V.
The ability to fit more cylinders in a smaller space distinguishes this arrangement from other engine designs. i.e., more power without sacrificing the car’s aesthetic appeal.
The V Engine is more prone to vibrations than a straight engine, and because of its more complex construction, repairs are more expensive. However, because every piston completes its power stroke in a shorter amount of time, this type of architecture generates greater power.
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Types of IC Engine by Configuration
The number of cylinders and engine layout determine an engine’s power and performance. This has a great effect on its fuel efficiency, sound, and power output.
However, high-tech fuel injection systems and other efficient engine parts make even smaller engines give higher outputs compared to larger engines. The following are the types of engines by configuration:
Twin Cylinders
These engine cylinder configurations are rare due to their capacity and low power output. It is found on the Fiat TwinAir car versions like the Fiat Panda Aria and Fiat 500 TwinAir. This is because the turbochargers make use of small, eco-friendly twin-cylinder engines.
Three Cylinder
Three-cylinder engines are mostly found on small cars but recently started appearing on larger family hatchbacks like the Ford Focus. The engine is known for its distinctive burbling noise and its shuddering vibration. This factor affects the engine balance.
Four Cylinder
The four-cylinder is the most common configuration that exists on the majority of small to mid-range cars. It offers a good amount of engine output, and the introduction of a turbocharger makes it more powerful. The engine is set in an inline layout.
Five Cylinder
These engine cylinder configurations are very rare. just like the three-cylinder engine, it also suffers vibration, leading to offset and imbalance of the engine, affecting its comfort and refinement.
Six Cylinder
Six-cylinder engines are typically configured in either a V or straight layout. Since the inception of the turbocharger, it has become a staple in high-performance and sports vehicles.
Historically, it has been established that six-cylinder engines were not regarded as the pinnacle of power.
Eight+ Cylinders
Engines featuring these cylinder configurations are typically arranged in a V formation, commonly known as V8, V10, and the newly introduced V12. Vehicles equipped with eight or more cylinders are commonly associated with high-performance supersport models.
The V12 stands as the largest engine configuration in use; however, the introduction of the Bugatti Veyron marked the debut of the sixteen-cylinder layout.
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How Does an Internal Combustion Engine Work?
A spark ignites a mixture of compressed air and gasoline vapor inside a temporarily sealed cylinder, setting off a series of processes that lead to the achievement of that goal. The cylinder then burns quickly. Because of this, the device is known as an internal combustion engine. The mixture expands as it burns, giving the car the power to move.
An automotive engine has two primary components: the cylinder block, which is the bottom, heavier element and serves as a housing for the majority of the engine’s moving parts, and the cylinder head, which is the higher, detachable cover.
The air and fuel mixture enters the cylinders through valve-controlled passageways in the cylinder head, while combustion-related gases are evacuated through other valve-controlled passages. The crankshaft, which resides in the block, converts the pistons’ reciprocating motion into rotary motion at the crankshaft.
You should watch the video below to learn how internal combustion engines works:
Conclusion
The internal combustion engine has been the driving force behind modern transportation for over a century. Its ability to convert chemical energy (from fuel) directly into mechanical energy through combustion within the engine cylinders has made it a highly efficient and compact power source for vehicles, machinery, and power equipment.
From gasoline and diesel engines to more advanced variants like turbocharged and hybrid systems, ICEs continue to evolve in terms of efficiency, emissions control, and performance.
While electric vehicles are gaining popularity, the internal combustion engine remains deeply integrated into global infrastructure, especially in sectors like transportation, agriculture, aviation, and power generation.
Continued innovation, including turbocharging, direct injection, and variable valve timing, ensures that ICEs will still play a vital role during the energy transition era.
FAQs
What is an internal combustion engine?
An internal combustion engine (ICE) is a type of engine where fuel combustion occurs inside the engine’s cylinders, producing energy that powers pistons or rotors to generate mechanical work.
What are the main types of internal combustion engines?
- Spark Ignition Engine (Petrol/Gasoline)
- Compression Ignition Engine (Diesel)
- Two-Stroke Engine
- Four-Stroke Engine
- Rotary (Wankel) Engine
How does an internal combustion engine work?
It follows a cycle (usually 4-stroke):
- Intake – Air-fuel mixture enters the cylinder
- Compression – The mixture is compressed
- Power (Combustion) – Ignition causes an explosion, pushing the piston
- Exhaust – Burnt gases are expelled
What fuels are used in ICEs?
Common fuels include gasoline, diesel, natural gas, biofuels, and sometimes ethanol blends.
What are the advantages of internal combustion engines?
- Compact and powerful
- Easy refueling
- Well-established infrastructure
- Suitable for long-distance and high-load applications
What are the drawbacks of ICEs?
- Produces emissions (CO₂, NOx, particulates)
- Less efficient than electric motors
- Requires more moving parts and maintenance
Are ICEs being phased out?
Many countries and automakers are planning a gradual phase-out of ICEs in favor of electric vehicles by the 2030s and beyond. However, ICEs will still be used in many industrial and off-road applications for years to come.
Can internal combustion engines be more environmentally friendly?
Yes, through fuel injection, turbocharging, catalytic converters, and using alternative fuels like compressed natural gas (CNG) or biodiesel, ICEs can achieve lower emissions and improved efficiency.