When a piece of sharp glowing piece metal or glowing ember of carbon lights the fuel mixture before it is time to it is called pre-ignition. Pre-Ignition does not nessecerily do damage to the engine apart from giving poor performance for the fuel used, but there can be a flow-on effect from Pre-igntiion. It can cause two fires to light in the combustion chamber. With the two fires aproaching eachother from different directions, the mixture trapped between them is squeezed between them quickly building heat and pressure until it detonates. Pinging is an often used term to describe an engine rattle when accellerating. The term "pinging" is often confused between Pre-Ignition and Detonation. Pre-Ignition will cause a loss of performance as the pressure rise that does the work is mistimed. Detonation is an severe impact taken inside the cylinder, more like an explosion than a controlled burning of gases.
The undesirable ignition of the air-fuel mixture before the spark is introduced. This can lead to detonation.
Undesirable condition in which the fuel mixture ignites early in the combustion chamber, possibly because of hot carbon deposits.
Situations where ignition of the fuel/air mixture occurs before it is supposed to. Indicates the combustion chamber is too hot. The heat range of the plug may be too hot for the application.
Ignition of a fuel-air mixture in an internal combustion engine (gasoline) before the spark plug fires. It can be caused by a hot spot in the combustion chamber or a very high compression ratio. Pre-ignition reduces power and can damage the engine.
Ignition of fuel before it is fully compressed in the cylinder. See also: DETONATION.
A sound that occurs in the cylinders when the fuel/air mixture is ignited too soon and the subsequent explosion hits the piston as it travels up the cylinder on the compression stroke. Usually, it's due to faulty timing, low- octane gas, or fragments of burning carbon in the cylinders. Also called pinging or pre-ignition. It sounds like marbles rattling in a can and can be heard best when accelerating up hills. This sound can also be caused by impending mechanical failure within the engine due to extreme wear of a piston or bearing.
Burning of fuel mixture before timed spark.