spark plug: Quick Facts

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Facts

Also Known As	sparking plug

Photos

Diagram of a car highlighting its electrical system, with labeled components such as the instrument panel, ignition system, battery, fuse blocks, wiring harnesses, and spark plugs, showing how power is distributed to various vehicle functions.

internal-combustion engine: four-stroke cycle

Diagram of a gasoline engine showing a cross-section of a piston and cylinder. Key parts such as the spark plug, valves, camshaft, piston, connecting rod, and crankshaft are labeled.

Labeled cross-sectional diagram of a V-type gasoline engine for an automobile, showing internal components such as pistons, crankshaft, camshaft, intake and exhaust valves, connecting rods, spark plugs, and intake manifold.

Diagram showing three stages in the operation of a Wankel rotary engine: intake of fuel-air mixture, ignition by spark plug, and exhaust release, with labeled parts and rotary motion indicated.

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Topics

spark gap ignition system

Key People

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Robert Bosch

German engineer