What is the normal idle speed for a sedan?
2 Answers
Car idle speed is generally normal at 700-800 RPM. Detailed introduction about idle speed is as follows: 1. Definition: The idle speed of a car refers to an operating condition. When the engine is running without load, it is called idling, meaning the car is in neutral gear. The engine speed during idling is referred to as idle speed. Idle speed can be adjusted by modifying the throttle opening size. Idling means the engine is "running without doing work." 2. Normal idle speed: When the vehicle is stationary and the engine is started, the minimum stable operating speed of the engine is called parking idle speed (the process of the engine transitioning from cold idle speed to reaching the normal operating temperature idle speed is called warm-up or heating up).
Over years of driving experience, I've observed that the normal idle speed for sedans typically ranges between 600 to 1000 RPM, depending on the engine's condition. During a cold start, the RPM tends to be higher, around 800-1200 RPM, to help the engine warm up quickly and protect its components. Once the engine reaches operating temperature, it stabilizes at around 700-800 RPM. If the idle speed fluctuates significantly or falls outside this range, it could indicate issues such as excessive carbon buildup in the throttle body, a dirty air filter, or worn-out spark plugs, all of which can affect RPM stability. I recommend making it a habit to check the tachometer while driving. Prolonged idling not only wastes fuel but also accelerates part wear. By the way, running the air conditioning may cause a slight increase of 50-100 RPM, which is a normal response from the control system. Regular maintenance, including carbon cleaning and sensor checks, ensures the idle speed remains healthy. If you notice any abnormalities, it's best to visit a repair shop early to prevent minor issues from becoming major problems.
