Car Spark Plug Maintenance Knowledge

(1) The spark plug is severely ablated. The top of the spark plug is scarred or damaged, or the electrode is melted or ablated.
(1) The electrode melts and the insulator turns white. Indicates that the temperature in the combustion chamber is too high. This may be caused by excessive carbon deposits in the combustion chamber, causing the valve clearance to be too small, causing the exhaust valve to overheat or the cooling device to work poorly. It may also be that the spark plug is not tightened to the specified torque, etc.
(2) The electrode becomes rounded and the insulator has scars. Indicates that the engine is pre-igniting, possibly because the ignition time is too early or used. The gasoline grade is too low, the calorific value of the spark plug is too high, etc.;
(3) The top of the insulator is broken. Detonation combustion is the main cause of insulator rupture. The ignition time is too early and the gasoline grade is low. , the temperature in the combustion chamber is too high, which may cause engine knocking and combustion.
(4) There are gray and black stripes on the top of the insulator. This stripe indicates that the spark plug is leaking and should be replaced with a new one.
(2) The spark plug has deposits. There is sometimes deposits stuck between the tip of the spark plug insulator and the electrode.
(1) Oily deposits. Oily deposits on the spark plug indicate that lubricating oil has entered the combustion chamber. If it's just a few spark plugs, the valve stem oil seal may be damaged. If the spark plugs of each cylinder are stuck with this kind of deposit, it indicates oil leakage in the cylinder, and the air filter and ventilation device should be checked to see if they are blocked.
(2) Black sediment. There are black deposits on the electrodes and inside of the spark plug, indicating that the mixture is too rich. Increasing the engine speed and continuing for every minute can burn off a layer of black soot left on the electrodes.