Which Consumes More Fuel: Idling or Driving?
2 Answers
Idling consumes more fuel than normal driving. In idle mode, the engine needs to maintain its rotation speed to prevent stalling. Typically, a car's idle speed is set at 800 rpm, requiring 1600 fuel injections per minute. During idling, the engine must remain ready for the driver's acceleration operation. When starting the car from a standstill, the engine needs to produce more torque than during normal driving. Due to the inherent programming of the car's electronic fuel injection system, the fuel injector dispenses slightly more fuel per cycle during idling compared to normal driving. The higher engine speed during idling results in increased fuel consumption. Idle state refers to a condition where the engine runs without load. When the accelerator pedal is fully released while the engine is running, it enters idle mode. Adjusting the idle speed should avoid sudden fluctuations, as this can cause premature engine wear. It's best to have the idle speed adjusted at an automotive service center. Idling means the engine operates without external load, only overcoming internal friction resistance, and does not output power. The minimum stable engine speed under these conditions is called idle speed, which is one of the five basic engine operating conditions. For a well-functioning engine, the idle speed typically ranges between 550 to 800 revolutions per minute.
The question of whether idling or driving consumes more fuel is quite interesting. As an ordinary driver, I've found that it really depends on the specific situation. When a car is idling without moving, such as waiting too long at a traffic light, the engine is running but not actually moving the vehicle, which wastes fuel - potentially burning about one liter of gasoline per hour. In comparison, when driving steadily on the road at a constant speed of 60-80 km/h on highways, the engine operates more efficiently, consuming much less fuel per kilometer and being more fuel-efficient overall. However, if you're stuck in stop-and-go city traffic with frequent acceleration, that actually burns more fuel than idling. Therefore, I recommend avoiding prolonged idling whenever possible, especially when using air conditioning in summer - turn off the engine if parked for more than one minute. This can save significant fuel costs and reduce environmental pollution. Maintaining steady speeds while driving and avoiding sudden braking are small habits that can help you get dozens of extra kilometers from each tank of fuel.
