Car shock! There are many reasons. For example, the throttle is dirty and the spark plug is broken. How to accurately judge whether it is a spark plug problem or a throttle problem?

It is the most effective method to judge the carbon deposition or damage of spark plugs by plugging and unplugging high-voltage lines. When the high-voltage wire of the spark plug is pulled out, the engine speed changes obviously, indicating that the spark plug has no carbon deposit or is in good condition. When the high-voltage wire of the spark plug is pulled out, the engine speed does not change or change obviously, indicating that the spark plug is organic carbon or damaged. When the high-voltage wire of the spark plug is slowly plugged into a certain position, the engine speed suddenly becomes very stable. The spark plug must be damaged and needs to be replaced.