Final answer:
The part that connects the piston and the crankshaft in an engine is the connecting rod, playing a vital role in the four-stroke combustion cycle.
Step-by-step explanation:
The part of an engine, pump, or compressor that connects the piston and the crankshaft is known as the connecting rod. In a four-stroke internal combustion gasoline engine, this component is crucial for translating the linear motion of the piston into the rotary motion of the crankshaft, which is an essential part of the engine's functioning. The whole process involves several strokes: the intake stroke where air is mixed with fuel, the compression stroke where the mixture is compressed, the power stroke where the fuel is ignited and work is done on the gas, and finally, the exhaust stroke that expels gases and prepares the engine for the next cycle.