What is the function of the exhaust stroke?

[OJake]

The function of the exhaust stroke is to expel exhaust gases. Below is a detailed introduction to the four-stroke engine: Classification: The four-stroke engine belongs to the reciprocating piston-type internal combustion engine. Depending on the type of fuel used, it is divided into three categories: gasoline engines, diesel engines, and gas-fueled engines. Piston-type internal combustion engines that use gasoline or diesel as fuel are called gasoline engines or diesel engines, respectively. Piston-type internal combustion engines that use natural gas, liquefied petroleum gas, or other gaseous fuels are called gas-fueled engines. Both gasoline and diesel are petroleum products and are traditional fuels for automobile engines. Non-petroleum fuels are called alternative fuels. Engines that burn alternative fuels are called alternative fuel engines, such as ethanol engines, hydrogen engines, and methanol engines. Working process: A four-stroke gasoline engine completes one working cycle through four strokes: intake, compression, power, and exhaust. During this process, the piston moves up and down four times, and the corresponding crankshaft rotates two revolutions.