In 1860 Étienne Lenoir used an electric spark plug in his gas engine, the first internal combustion piston … See more

The function of a spark plug is to produce a spark at the required time to ignite the combustible mixture. The plug is connected to the high voltage generated by an ignition coil or magneto. As current flows from the coil, a volta… See more

A spark plug is composed of a shell, insulator and the central conductor. It passes through the wall of the combustion chamber and therefore must also seal the combustion chamber against high pressures … See more

The operating temperature of a spark plug is the actual physical temperature at the tip of the spark plug within the running engine, normally between 500 and 800 °C (932 and 1,472 °F). This is important because it determine… See more

The spark plug's firing end will be affected by the internal environment of the combustion chamber. As the spark plug can be removed for inspection, the effects of combustion on the plug can be examined. … See more

"Indexing" of plugs upon installation involves installing the spark plug so that the open area of its gap, not shrouded by the ground electrode, faces the center of the combustion chamber rather than one of its walls. The t… See more