What is the normal RPM for an automatic transmission car?
2 Answers
For an automatic transmission car, maintaining a stable RPM between 1800~2000 is considered normal. Relevant information is as follows: 1. RPM: The engine speed affects the number of work cycles per unit time or the effective power output of the engine, meaning the effective power varies with different RPMs. Therefore, when specifying the effective power of an engine, the corresponding RPM must also be indicated. 2. Introduction: The effective power and its corresponding RPM specified on the engine's product label are referred to as the rated power and rated speed, respectively. The operating condition of the engine at the rated power and rated speed is called the rated condition. The rated power is not the maximum power the engine can produce; it is the maximum usable limit of effective power determined based on the engine's intended use.
As someone who has driven automatic transmission cars for over a decade, I think the normal RPM range is quite broad and mainly depends on what you're doing. When idling at a stop, engine RPM between 600 to 1000 is normal as long as the car remains stable without shaking. During acceleration for overtaking or climbing hills, the RPM may surge above 2000 or even 3000, and it's perfectly normal for the transmission to automatically shift gears to bring it down. When cruising at highway speeds of 120 km/h, the RPM typically stays around 2000 to 2500 for optimal fuel efficiency, so there's no need to worry too much. However, if the idle RPM drops below 600 and the car tends to stall, or if it exceeds 1000 with a humming noise, it's time for a check-up—it could be due to a dirty throttle body or sensor issues. Regular maintenance can help avoid these minor problems.
