Xichai 420 HP engine dithered from 1 100 to 1200. What is the reason?

If it is idle jitter, it is necessary to check whether the throttle is too dirty or faulty, and whether the rubber parts inside the engine bracket are aging. If it is vibration during driving, in addition to the faulty parts that vibrate during idling, it is also necessary to check whether the tire dynamic balance is normal, whether the tire tread is uneven, and whether the wheel bearings are aging.

After the engine works for a long time, there is usually a thick layer of deposit attached to the throttle position, which may be oil vapor or carbon deposit. Too much throttle deposit will inevitably affect the intake fluidity inside the engine block, and the intake system will fluctuate. However, the fuel injection quantity of the engine is adjusted too late, which will naturally disturb the air-fuel ratio inside the engine block and lead to engine idling jitter.