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Related to preignition: Spark knock


The ignition of fuel in an internal-combustion engine before the spark passes through the fuel, resulting from a hot spot in the cylinder or from too great a compression ratio for the fuel.


(ˌpri ɪgˈnɪʃ ən)

ignition of the charge in an internal-combustion engine earlier in the cycle than is compatible with proper operation.


[ˌpriːɪgˈnɪʃən] Npreignición f
References in periodicals archive ?
The British engine boffins achieved this transformation by remapping the engine management system to squirt more fuel into the cylinders for preignition.
However systems of this type have not yet been utilized in practice, except that lead tetraethyl has been used to modify the preignition knocking phenomena of internal combustion systems.
This deposit tends to block proper heat transfer out of the cylinder, raising temperatures throughout the combustion cycle and increasing the tendency toward detonation or preignition.
The "ping" associated with low-grade fuel in a car can become preignition and explosive detonation in an aircraft engine after only seconds of high-power operation, causing engine failure.