Engine Basics – Explained Simply An engine is the heart of your vehicle, converting fuel into the power that keeps you moving. Most modern vehicles use an internal combustion engine, operating through a precise four-stroke cycle: intake, compression, power, and exhaust. Inside the engine, key components like pistons, cylinders, crankshaft, camshaft, and valves work together thousands of times per minute to generate smooth, reliable performance. Proper lubrication and cooling are essential.