What is the reason why the alarm clock seems to go off on the Nissan sunshine car?

First, check whether the oil is between two points at the bottom of the dipstick. If it is less, add some oil first to see if there will be noise.

Because the noise of the engine is usually caused by insufficient lubrication, or valve vibration, or tappet and tappet vibration, the only solution is to take the engine apart and check whether it is damaged or loose. Then you said there would be a lot of noise inside the car. Is it because the sound insulation layer inside the car is damaged, which is also commonly known as floor glue? As for the adjustment of the throttle.

If you know where the throttle is, you should see a lever on it to control the throttle switch. Adjusting the throttle is to control the throttle opening. You can adjust it by tightening or loosening the next screw, usually a positive thread.