A spark plug for an automotive engine includes a shell housing, and an insulator within the shell housing but extending axially beyond the shell housing. A terminal, referred to herein as a cup post terminal, is fixed to the proximal end of the insulator. The cup post terminal includes an engagement surface configured to engage an ignition coil spring for energy transfer to initiate a spark. The cup post terminal includes a sidewall extending axially from the engagement surface. The sidewall cooperates with the engagement surface to define a pocket for the ignition coil spring. The sidewall can have drainage openings to allow oil or contaminants to escape the pocket and drain away from the engagement between the engagement surface and the ignition coil spring. The engagement surface can also be sloped to facilitate the drainage toward the drainage openings.

A device that includes a window, a catalyzed layer, and a laser source is disclosed. The window may include a first surface and a second surface. The catalyzed layer may be disposed on the first surface of the window. The catalyzed layer may include a compound having a threshold transmittance, and be configured to cause a reaction with soot in one or more of a combustion chamber or a pre-combustion chamber of a combustion engine at an activation temperature to reduce accumulation of soot on the window. The laser source may be disposed relative to the second surface of the window, and configured to emit a laser beam through the window and the catalyzed layer. The laser beam may be configured to cause ignition of an intake charge of one or more of the combustion chamber or the pre-combustion chamber.

A spark plug is disclosed that includes at least one bore extending through a shell of the spark plug in order to form a passageway between an annular volume around the spark plug insulator nose and a pre-chamber volume of a pre-chamber device, thus directing a purge of exhaust gases trapped in the annular volume to a space formed by the exterior of the spark plug body and the interior of the pre-chamber device.

A spark plug is disclosed that includes at least one bore extending through a shell of the spark plug in order to form a passageway between an annular volume around the spark plug insulator nose and a pre-chamber volume of a pre-chamber device, thus directing a purge of exhaust gases trapped in the annular volume to a space formed by the exterior of the spark plug body and the interior of the pre-chamber device.

A spark plug includes an insulative sleeve. A glaze coating is disposed on an exterior surface of the insulative sleeve. The glaze coating includes a boric acid, a borosilicate glass, a barium borate glass, a phosphorous glass, a silicate glass, or a combination thereof. The glasses are independently modified with a modifier selected from the group consisting of alkali group metals, alkali earth group metals, aluminum, silicon, a halogen, or a combination thereof. The glaze coating has a softening point between about 650° C. and about 1100° C.

A spark plug includes an insulative sleeve. A glaze coating is disposed on an exterior surface of the insulative sleeve. The glaze coating includes a boric acid, a borosilicate glass, a barium borate glass, a phosphorous glass, a silicate glass, or a combination thereof. The glasses are independently modified with a modifier selected from the group consisting of alkali group metals, alkali earth group metals, aluminum, silicon, a halogen, or a combination thereof. The glaze coating has a softening point between about 650° C. and about 1100° C.

A spark plug is described as including an insulator which is situated in a spark plug housing and which has a longitudinal axis and an opening along the longitudinal axis. Furthermore, a center electrode is situated in the opening of the insulator. Furthermore, at least one ground electrode is provided at the spark plug housing. The insulator has a first insulator section and a second insulator section, the first insulator section extending in the direction of the longitudinal axis over a first insulator section length having a first inner diameter. The second insulator section extends in the direction of the longitudinal axis over a second insulator section length having a second inner diameter. Here, the first inner diameter is smaller than the second inner diameter, the first insulator section merging directly into the second insulator section. The center electrode has a center electrode section which extends in the direction of the longitudinal axis over a center electrode section length having a center electrode outer diameter at least over the entire insulator section length of the first insulator section and of the second insulator section.

A spark plug is described as including an insulator which is situated in a spark plug housing and which has a longitudinal axis and an opening along the longitudinal axis. Furthermore, a center electrode is situated in the opening of the insulator. Furthermore, at least one ground electrode is provided at the spark plug housing. The insulator has a first insulator section and a second insulator section, the first insulator section extending in the direction of the longitudinal axis over a first insulator section length having a first inner diameter. The second insulator section extends in the direction of the longitudinal axis over a second insulator section length having a second inner diameter. Here, the first inner diameter is smaller than the second inner diameter, the first insulator section merging directly into the second insulator section. The center electrode has a center electrode section which extends in the direction of the longitudinal axis over a center electrode section length having a center electrode outer diameter at least over the entire insulator section length of the first insulator section and of the second insulator section.

An ignition apparatus for an internal combustion engine includes a center electrode, a ground electrode, an insulator, a housing, and an insulator protective wall portion. The ground electrode is disposed such that a discharge gap is formed between the ground electrode and the center electrode. The insulator holds the center electrode on an inner side of the insulator. The housing holds the insulator on an inner side of the housing. The insulator protective wall portion is arranged to surround an outer circumference side of a distal end portion of the insulator. A distal end of the insulator protective wall portion is positioned further towards a distal end side than a distal end of the insulator is and further towards a proximal end side than a distal end of the center electrode is. The insulator protective wall portion includes an inward protruding portion that protrudes towards a side surface of the center electrode.

Methods and systems are provided for controlling spark plug fouling in newly manufactured vehicles. In one example, an engine is operated with a first, more aggressive spark discharge schedule when in a pre-delivery state and transitioned to a second, less aggressive spark discharge schedule when in a post-delivery state. In each spark discharge schedule, a spark plug ignition coil is repeatedly discharged when the engine is off, such as when the engine is spinning down to rest on a shutdown event or before the engine is fueled on an engine restart event.