What is the idle speed of an automatic transmission car?

[SanNathan]

Automatic transmission cars typically idle at around 5 to 10 km/h, depending on the specific model. Below is relevant information about idle speed: Idle speed under different conditions: Generally speaking, automatic transmission cars have slightly higher engine RPM at idle compared to manual transmission cars, usually between 800 to 1000 rpm. When idling in D gear without pressing the accelerator, the speed is approximately 5 to 10 km/h. Automatic transmission idle state: This refers to an operating condition where the engine of an automatic transmission car runs without load. When the accelerator pedal is completely released while the engine is running, the engine enters idle state. During idle speed adjustment, the RPM should not fluctuate abruptly as this may cause premature engine wear. It's recommended to have the adjustment performed at an automotive service center.

[OElliot]

I remember when I drove my old car, the idle speed was usually around 750 RPM, and it sounded smooth as long as the engine noise was steady. My modern automatic transmission car is the same, maintaining 650-800 RPM when stopped in D gear, which is the standard range. Actually, an idle speed that's too low can make acceleration sluggish, while slightly higher can waste fuel. Once I noticed the idle speed drifting above 900 RPM, and after visiting the repair shop, I found it was due to the added load from the air conditioning system. I recommend listening to the engine sound every time you start the car to ensure it's even, avoiding excessively high idle speeds to reduce fuel consumption and extend engine life. When changing the oil, have the technician check the idle speed sensor as well to ensure stability. For daily driving, keeping the idle speed under 800 RPM is ideal.

[LydiaRose]

The idle speed of modern automatic cars is typically set around 700 RPM. My car idles at 750 RPM, which feels quite appropriate. This is all thanks to ECU control, which adjusts based on temperature. During cold starts in winter, it may rise to 1000 RPM and then drop back to normal once the engine warms up. I've driven various cars, and idle speeds generally fluctuate between 600 and 800 RPM, with gasoline engines slightly higher and diesel engines slightly lower. If the tachometer shows significant RPM fluctuations, it might indicate worn spark plugs or intake issues, so it's worth checking the air filter. Remember, normal idle conditions feature low engine noise and fuel consumption, and occasional highway driving can make it even more stable. It's best to monitor the RPM at red lights to prevent it from dropping below 600, which could cause stalling and affect driving safety.

[StFinn]

My automatic transmission car idles at around 700 RPM when parked, and I've heard most cars are similar. Checking the tachometer, if it's between 600 and 800 RPM, it's fine. If it's too high, it burns more fuel, and if it's too low, it may cause shaking. A simple method is to wait 2 minutes after a cold start and listen to the engine sound - if it's steady, no worries. If it's unstable, get it checked promptly as the throttle body might be dirty. You'll get used to it after driving for a while.