Car spark plugs are not a minor problem and need to be dealt with in time

When maintaining a car, more attention should be paid to the condition of the spark plug, and a spark plug with excellent performance can improve the vehicle's dynamic performance.

Under normal circumstances, the spark plug has a service life of 15,000 kilometers and the long-acting spark plug has a service life of no more than 30,000 kilometers. However, many owners of spark plugs often have problems like this, failing to reach their normal service life.

In fact, the working temperature of spark plugs is quite high. When the engine is running normally, the temperature of the spark plug insulator skirt is generally kept between 500 and 600 degrees Celsius. Excessively high or low temperature has no effect on the spark plug. When the temperature of the spark plug is too low, the insulator on the spark plug is likely to deposit carbon, eventually causing leakage and even causing a misfire. If the operating temperature of the spark plug is too high, pre-ignition and engine knock can easily occur. In the Chery Automobile Training Camp, the staff of the store grouped the common failures of spark plugs into two types. One is severe ablation of spark plugs, and the other is deposits of spark plugs.

Spark plug ablation When the owner discovers that the spark plug has scars or damages at the top, the electrode appears molten, and the ablation phenomenon shows that the spark plug has been destroyed, and the spark plug should be replaced at this time. During the replacement process, the owner can check the spark plug ablation symptoms and changes in color.

Symptom 1: The electrode melts and the insulator is white. Diagnosis: This phenomenon indicates that the temperature in the combustion chamber is too high. This may be due to too much coke in the combustion chamber, resulting in too small a valve clearance, further causing overheating of the exhaust valve or poor operation of the cooling device. When the spark plug is not tightened according to the specified torque, the electrode will melt and the insulator will appear white.

Symptom 2: The electrode becomes round and the scarring of the insulator is diagnosed: This indicates that the engine is pre-ignited, which may be caused by premature ignition, low octane value of the gasoline, or excessive heat value of the spark plug.

Symptom 3: Insulator Tip Fragmentation Diagnosis: In general, knocking combustion is the main cause of insulator breakdown. The ignition timing is too early, the octane number of gasoline is low, and the temperature in the combustion chamber is too high, which may cause the engine to knock and burn.

Symptom 4: There is gray-black streaks at the top of the insulator Diagnosis: The presence of this streaking indicates that the spark plug has leaked and the owner needs to replace the new item unconditionally.

Spark plugs have deposits on the top of the spark plug insulators and sometimes deposits between the electrodes. Owners should not underestimate this deposit.

In severe cases, this condition may cause the engine not to work properly. After cleaning the spark plugs, the vehicle can be operated normally for a while, but something similar will happen soon. In fact, the presence of deposits in spark plugs is only a surface phenomenon, which may be a sign of problems with other mechanical parts of the vehicle.

Symptom 1: Oily deposits on the spark plug Diagnosis: When an oily deposit appears on the spark plug, it indicates that the oil has entered the combustion chamber. If only a few spark plugs have oily deposits, damage to valve stem seals may be caused. However, if the spark plug of each cylinder sticks to this kind of deposit, it indicates that the cylinder has oil. In general, in the case of air filter and ventilation device plugged, the cylinder is prone to oleophobic phenomenon.

Symptom 2: The black plug on the spark plug Diagnosis: There is a black deposit inside the spark plug electrode and it usually indicates that the gas mixture in the cylinder is too thick. The owner can increase the speed of the engine and continue for a few minutes to burn off a layer of black soot that remains on the electrodes.