( Automotive engineering : Vehicle components , Engine, transmission, and exhaust ) ignition1, ignition2, ignition3 Pre-ignition
is a situation in which the fuel-air mixture in a spark
ignition engine ignites
before the timed spark, because of contact
with a hot
Over-heated spark plugs and exhaust valves are the main causes of pre-ignition.
Pre-ignition might be the consequence of the spark plug tip getting too hot.
Thermal coatings also resist detonation and pre-ignition by keeping metal hot spots from forming on piston crowns or head chambers.
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