Gasoline and diesel vehicles are similar. They both use internal combustion engines. A gasoline car typically uses a spark-ignited internal combustion engine, rather than the compression-ignited systems used in diesel vehicles. In a spark-ignited system, the fuel is injected into the combustion chamber and combined with air.
Although gasoline is the most common transportation fuel, there are alternative fuel options that use similar components and engine systems. Combustion chamber This is one of the most vital parts of the engine Everything must come together perfectly for good performance. Learn more. Get more out of every trip Explore our comprehensive list of tips to help you improve fuel efficiency and get more out of every trip.
Imperial Oil, licensee. Actual benefits vary depending on factors such as vehicle type, driving style, and gasoline previously used. What powers those pistons up and down are thousands of tiny controlled explosions occurring each minute, created by mixing fuel with oxygen and igniting the mixture. Each time the fuel ignites is called the combustion, or power, stroke.
The heat and expanding gases from this miniexplosion push the piston down in the cylinder. Almost all of today's internal-combustion engines to keep it simple, we'll focus on gasoline powerplants here are of the four-stroke variety. Beyond the combustion stroke, which pushes the piston down from the top of the cylinder, there are three other strokes: intake, compression, and exhaust.
Engines need air namely oxygen to burn fuel. During the intake stroke, valves open to allow the piston to act like a syringe as it moves downward, drawing in ambient air through the engine's intake system. When the piston reaches the bottom of its stroke, the intake valves close, effectively sealing the cylinder for the compression stroke, which is in the opposite direction as the intake stroke.
The upward movement of the piston compresses the intake charge. In today's most modern engines, gasoline is injected directly into the cylinders near the top of the compression stroke. Other engines premix the air and fuel during the intake stroke. In either case, just before the piston reaches the top of its travel, known as top dead center, spark plugs ignite the air and fuel mixture. The resulting expansion of hot, burning gases pushes the piston in the opposite direction down during the combustion stroke.
This is the stroke that gets the wheels on your car rolling, just like when you push down on the pedals of a bike. When the combustion stroke reaches bottom dead center, exhaust valves open to allow the combustion gases to get pumped out of the engine like a syringe expelling air as the piston comes up again.
When the exhaust is expelled—it continues through the car's exhaust system before exiting the back of the vehicle—the exhaust valves close at top dead center, and the whole process starts over again. In a multicylinder car engine, the individual cylinders' cycles are offset from each other and evenly spaced so that the combustion strokes do not occur simultaneously and so that the engine is as balanced and smooth as possible.
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