Leaving a diesel vehicle idling overnight can lead to carbon buildup, oil leakage, and engine damage. Below is more detailed information: 1. Vehicle Idle Speed: Vehicle idle speed refers to an operating condition. When the engine runs without load, it is called idling, meaning the vehicle is in neutral gear. The engine speed during idling is referred to as idle speed. The idle speed can be adjusted by altering the throttle opening size, among other methods. Idling essentially means the engine is "running without doing work." When the engine is operating, if the accelerator pedal is fully released, the engine enters an idle state. Adjusting the idle speed should avoid sudden increases or decreases in RPM, as this can cause premature engine wear. It is best to have this adjustment performed by an automotive repair service. 2. Normal Idle Speed: When the vehicle is parked 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 a cold idle state to reaching the idle speed at normal operating temperature is called warming up or heating up). 3. Driving Idle Speed: When the vehicle 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 referred to as driving idle speed.
