Is It Normal for the Engine to Shake When Turning on the AC in a New Car?

[JackRose]

It is a normal phenomenon. When the car is in an idle state, the engine continues to run, and shaking when the AC is turned on is quite normal. Idling is a working condition of the car, referring to the engine running in neutral gear. The engine speed during idling is called the idle speed. The idle speed can be adjusted by modifying the throttle opening size, among other methods. Below is additional information about idling: Normal Idling: When the vehicle is parked and the engine is started, the minimum stable engine speed is referred to as parking idle (the process of transitioning from a cold engine idle state to an idle state where the engine reaches normal operating temperature is called warming up or heating the engine). Driving Idle: When the car is in gear, without pressing the accelerator pedal or releasing it while driving, maintaining the minimum throttle opening, the engine speed matches the parking idle speed. This state is called driving idle.