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
MSD Ignition of Fame in 2009 in recognition of how the company has helped to shape the American racing industry. MSD also received honors as the SEMA manufacturer of the year in both 2005 and 2007. The current president of the company, Russell Stephens, has also served on the board of directors for SEMA (2002-2006). MSD Ignition MSD Ignition is an American automotive aftermarket manufacturing company that specializes in high-end ignition system and electrical components. MSD Ignition was the first company in the world to experiment with Multiple Spark Discharge for the ignition system of internal combustion engines in 1970. The idea