Also found in: Encyclopedia, Wikipedia.
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 mathematical model can be used to help in the design of a spark ignition engine for alternative fuels as well as to study various problems such as pollutant emissions, engine performance, preignition, knocking and misdistribution of the fuel-air mixture.
As shortly mentioned in the introduction section, low speed preignition cylinder pressure cycles can be characterized by two main events: Pre-ignition and (mega) knock.
The steam vapor promoted a cooling effect, retarded preignition and served to keep the cylinder free of carbon.
The cylinder head displayed re-solidified, splattered metal around the sparkplug holes, valves, and valve seats, a feature consistent with preignition and/or detonation.
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.
An accelerometer is used to measure preignition in gasoline-burning engines.
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.
The fuel variable included the constant heat of preignition of dry fuels ([Q.
To reduce the tendency for preignition, motorists are required to use high-octane fuels, which are more expensive than regular fuels.
SAN ANTONIO -- Southwest Research Institute (SwRI) will launch a new consortium focusing on fuels and lubricants to discover ways to suppress low-speed preignition (LSPI), a condition that causes heavy engine knock and can seriously damage engine parts or cause complete engine failure.