Explaining Internal Combustion

Unless you drive a fully electric vehicle, your car generates power with an internal combustion engine. A lot of people, of course, only have a vague idea of what that means. This primer will introduce you to the key concepts that make your car go.

Steps in a Four-Stroke Engine

Explaining Internal Combustion - Auto USA

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Most of today’s engines rely on a piston system developed by Nikolaus Otto in 1876. His concept generates power through four steps: intake, compression, power, and exhaust. During the intake phase, an engine’s pistons move down to draw in a mixture of air and fuel. After drawing in the mixture, the piston pushes up to increase pressure. This compresses the mixture even more, making it ready for combustion. Once the piston reaches the top of its stroke, a spark plug ignites the compressed fuel. This stage creates the energy that powers your car. It also creates exhaust. The piston pushes this exhaust out throw a cam lifter, making room for the process to start again. If this sounds confusing, watch this animation to see how each step in the process works.

Direct Injection Gives Your Car the Right Mixture of Air and Fuel

While most of today’s engines follow Otto’s design, there have been plenty of innovations that make engines more efficient and powerful. Direct injection is one of the most useful features you will find in modern vehicles. It replaced the intake manifold found in older vehicles. Direct injection makes sure that your engine gets the perfect mixture of fuel and air. It monitors the engine’s needs as you drive to make adjustments as necessary. By monitoring the engine, direct injection can increase or decrease the amount of air added to gasoline. This process helps the engine produce more power while burning less fuel.

Turbochargers Make Small Engines Powerful

Turbochargers are primarily used to build small engines that generate large amounts of energy by forcing more air into the engine’s cylinders. Turbochargers aren’t found in all cars, but they are useful devices for people who want fuel-efficient performance vehicles. A turbocharger doesn’t technically make the engine more efficient. It does, however, make it possible for a smaller engine to do a larger engine’s job. In the end, you end up burning less fuel to get more power.

The Number of Cylinders in a Vehicle’s Engine

When you compare vehicles, you’ll notice that manufacturers make a big deal out of how many cylinders their engines have. Generally speaking, the more cylinders an engine has, the more power it can make. A four-cylinder engine has four pistons working inside four cylinders. They’re usually small and don’t generate a lot of power (unless they have turbochargers). A V6 engine has six cylinders, which means you get two more pistons generating power. You can even find vehicles, usually large SUVs, with V8 and V12 engines. These behemoths can make a lot of energy, but they also tend to burn a lot of fuel. Knowing how internal combustion works doesn’t make you a mechanic, but it will help you understand what your mechanic tells you. Besides, it’s satisfying to know how the things around you function.