What is the appropriate RPM when starting a car?
2 Answers
When starting a car, an RPM of around 1000 is considered appropriate and normal, as the engine typically doesn't rotate too fast during startup. The RPM varies depending on the engine's technical condition and starting resistance. For a new engine that hasn't been run-in, the starting resistance is higher, resulting in a correspondingly lower starting RPM. After running-in and proper maintenance, the coordination between moving parts reaches an optimal state, and the RPM may increase slightly. The engine's RPM is related to the number of power cycles per unit time or the effective power output of the engine. That is, the engine's effective power changes with different RPMs. Therefore, when specifying the engine's effective power, the corresponding RPM must also be indicated.
It's normal for the engine to rev higher when starting the car. My car usually starts at around 1500 to 2000 RPM, which helps the engine quickly warm up to operating temperature. After waiting for about half a minute to a minute, it gradually drops to a stable idle speed of 700 to 900 RPM. I've been driving for over a decade and always observe this behavior during startup. The colder the temperature, the higher the initial RPM tends to be—it might reach 1800 RPM in winter. The key is not to rush off; letting the car warm up protects the engine and reduces wear. If the RPM doesn't drop for a long time after starting or is too high (exceeding 2000 RPM), it could indicate a dirty throttle body or sensor issue that needs checking. Overall, don't worry too much; just let the RPM naturally decrease.
