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spark plug

Device that generates sparks in internal combustion engines

EntityQ193340

Also known as sparking plug

Subclass of: device
Part of: combustion engine
, gasoline engine
, internal combustion engine
+1 more

Overview

From Wikipedia, the free encyclopedia · Read full article · Text CC BY-SA 4.0

A spark plug is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/air mixture by an electric spark, while containing combustion pressure within the engine. A spark plug has a metal threaded shell, electrically isolated from a central electrode by a ceramic insulator. The central electrode, which may contain a resistor, is connected by a heavily insulated wire to the output terminal of an ignition coil or magneto. The spark plug's metal shell is screwed into the engine's cylinder head and thus electrically grounded. The central electrode protrudes through the porcelain insulator into the combustion chamber, forming one or more spark gaps between the inner end of the central electrode and usually one or more protuberances or structures attached to the inner end of the threaded shell and designated the side, earth, or ground electrode(s).

Overview

All data

31 statements · 32% with external sources · numbers in brackets are citations

Has effect: ignition

On other databases

26 identifiers linking spark plug across the web's reference databases

Data quality

statements

32%

externally sourced

Source last edited July 10, 2026. AIDB refreshes this page daily.

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AIDB. (2026). spark plug (Q193340). Retrieved from https://aidb.si/e/spark-plug-Q193340