After starting your car, the valves in its engine move, thus turning the shaft. A revolution is a complete turning of the crankshaft, and RPM is the number of times the crankshaft rotates in a single minute. Vehicles with higher RPMs require more fuel, making the engine overwork. If your car has an internal problem that makes it idle higher, it might have a higher RPM that jumps when you try accelerating. If your vehicle is exhibiting any of these signs, it might have one of the following issues that need to be addressed.