An Engine in an automobile relies on internal moving parts. One of these moving parts is the crankshaft and is the main moving part in the engine. The crankshaft rotates constantly when the engine is running. There are connecting rods and pistons attached to the crankshaft that rotate along with it.
There are also timing components that keeps the spark and valves in the right place at the right time. An oil pump provides lubricante to all the rotating parts.