What does idle speed mean?

Idle speed means that the engine runs with no load, and it only needs to overcome the friction resistance of its internal parts and does not output power. The lowest speed to maintain the stable operation of the engine is called idle speed, which is one of the five basic working conditions of the engine. The idle speed of an engine with good working performance is generally 550-800 rpm. Idle speed can be adjusted by adjusting throttle opening and idling oil supply. Generally speaking, the minimum idle speed is the best when the engine does not shake in the idle speed range and the acceleration performance is good. When idling, the engine only needs to overcome its internal friction resistance, no other load and no output power, which is one of the five basic working conditions of the engine. It can provide convenience for the owner to temporarily drive and stop under various circumstances, such as when waiting for a red light, it can prevent the engine from stalling and play the role of energy saving and emission reduction. Idle time should not be too long, too long idle time will produce carbon deposit in the car.