Spark plugs. General information (BMW 5 Series E34)

The spark plug consists of a central electrode, an insulator with a housing, and a ground electrode. The ground electrode is hermetically secured in the insulator, and the insulator is rigidly connected to the housing. A spark jumps between the central electrode and the ground electrode, which ignites the air-fuel mixture. The ease of starting the engine, its behavior in idle mode, acceleration, and maximum speed of the car depend on the spark plugs. Therefore, you should not deviate from the type of spark plugs recommended by the manufacturer without good reason, which is characterized by a heat rating. The heat rating is the degree of resistance of the spark plug to thermal loads in the engine under various operating conditions. Spark plugs are selected for the engine in such a way that their self-cleaning temperature is achieved under all conditions. The lower the heat rating of the spark plug, the higher the resistance to glow ignition and the less its resistance to contamination. The higher the heat rating of the spark plug, the lower the resistance to glow ignition and the greater its resistance to contamination.

(This publication was borrowed from an online resource «BMWMAN.ru»)