1, engine cylinder missing: Engine cylinder missing mainly refers to the abnormal operation of one or more cylinders of the engine, which is usually manifested by obvious intermittent exhaust airflow and severe vibration of the exhaust pipe, so the engine jitter can be obviously felt, sometimes accompanied by sudden noise. This is mostly related to ignition coil failure.
2. The machine foot glue is aging or loose: the machine foot glue is the glue block between the engine and the frame. Its function is to reduce the vibration and buffer when the engine works and fix the engine. Once these feet are aged or loose, the vibration of the engine will become very severe, and the effect will be much weakened after replacing the feet again.
3. Carbon deposition: Carbon deposition is always inevitable in automobiles, including cylinder carbon deposition, throttle carbon deposition, spark plug carbon deposition and intake carbon deposition. When the engine has too much carbon deposit, it will affect the ignition energy, intake efficiency and mixing ratio of the automobile, resulting in unstable power output and jitter when idling and accelerating. It is recommended to go to the 4S shop to clean the engine.