Pre-ignition Pre-ignition Pre-ignition (or preignition) in a spark-ignition engine is a technically different phenomenon from engine knocking, and describes the event wherein the air/fuel mixture in the cylinder ignites before the spark plug fires. Pre-ignition is initiated by an ignition source other than the spark, such as hot spots in the combustion chamber, a spark plug that runs too hot for the application, or carbonaceous deposits in the combustion chamber heated to incandescence by previous engine combustion events. The phenomenon is also referred to as 'after-run', or 'run-on' or sometimes dieseling, when it causes the engine to carry on running after
Archaic–Early Basketmaker Era Archaic–Early Basketmaker Era The Archaic–Early Basketmaker Era (7000 - 1500 BCE) was an Archaic cultural period of ancestors to the Ancient Pueblo People. They were distinguished from other Archaic people of the Southwest by their basketry which was used to gather and store food. They became reliant on wild seeds, grasses, nuts and fruit for food and changed their movement patterns and lifestyle by maximizing the edible wild food and small game within a geographical region. Manos and metates began to be used to process seeds and nuts. With the extinction of megafauna, hunters adapted their tools, using spears with