The reason for the abnormal shaking is that the newly installed spark plug being polluted by carbon deposit damage from the above analysis.
Where does the spark plug carbon deposition come from and its adverse reactions
When the spark plug is working inside the engine, if the self-cleaning temperature cannot be reached, its insulator protrusion will be covered by impurities or carbon deposit. 450 Celsius degrees is the self-cleaning temperature, which means that the carbon deposit can be burned off at or above this temperature when working in the engine.
Therefore, if the vehicle continues to travel at a low speed and a short distance, the spark plug cannot reach the self-cleaning temperature, thus carbon deposits are easily generated. Once the insulator gets polluted, it will cause power leakage. The leaked ignition voltage enters the metal housing along the fouling surface, running away with the vehicle body to ground, rather than breaking through the ignition gap to normal ignition.
Another reason for carbon deposits is not installing spark plugs with the right heat value. Spark plugs can be same from the appearance while with different heat value. So it is very important to chose the right heat value.
Solution to avoid carbon deposits:
1. Regularly check and replace the ignition system components (ignition coil, high voltage line, high voltage cap)
2. In order to avoid the problems caused by low speed or short distance driving, try to speed up or drive long distance from time to time.
3. Ensure that the spark plug uses the correct thermal value of the spark plug.
When there is carbon deposit on the spark plug, please replace the spark plugs in time!