What is spark

spark test

Glossary “spark test” Definition:
A quick check of the ignition system made by carefully placing a metal end of one of the spark plug wires close to the engine while cranking the engine to see if there is a spark gap and to determine its intensity.

spark plug fouling

Glossary “spark plug fouling” Definition:
An accumulation of deposits on the lower, exposed end of the spark plug that act as an electrical conductor, thereby creating a path for electricity to travel to ground, rather than jump across the electrode gap.

spark plug heat range

Glossary “spark plug heat range” Definition:
The temperature limits, hot, normal, or cold, within which a spark plug is designed to operate. It is determined by varying the length of the exposed lower section of the plug ceramic insulator.

spark line

Glossary “spark line” Definition:
The line on an oscilloscope that indicates the voltage required to fire the spark plug and the number of degrees the distributor turns while the spark exists.

Spark Output

Glossary “Spark Output” Definition:
Ford SPOUT. The output signal from the processor which triggers (signals) the ignition module to fire the ignition coil.

spark plug

Glossary “spark plug” Definition:
An ignition component threaded into the cylinder head that contains two electrodes extending into the cylinder that form a gap across which high-voltage electricity arcs to ignite the compressed A/F mixture.

spark delay valve (SDV)

Glossary “spark delay valve (SDV)” Definition:
A vacuum valve acting like a restrictor, used in the vacuum line between the distributor and carburetor, to delay vacuum-timing advance under certain driving conditions to reduce NOx emissions.

spark knock

Glossary “spark knock” Definition:
Term used for detonation or ping. Secondary rapid burning of the A/F mixture in the combustion chamber causing a second flame front that collides with the first flame front and produces a engine knock.

spark decel valve

Glossary “spark decel valve” Definition:
A vacuum valve, located in the line between the distributor and carburetor, to advance the spark during deceleration, to reduce emissions.

spark advance curve

Glossary “spark advance curve” Definition:
The rate at which ignition timing advances as plotted on a graph; the line rises from some initial amount of advance and levels off at the maximum advance.