New cars are trending towards downsized turbocharged engines using direct injection. While these engines offer better efficiency and fuel economy, this trend has increased the likelihood of engines experiencing destructive super knock, which results from LSPI.
Low Speed Pre-Ignition (LSPI) isn’t fully understood, but it can result in knock occurring, potentially destroying pistons, connecting rods, and spark plugs. Watch the video from Engineering Explained for more info:
Light knock and super knock are different in how they occur in respect to spark plug timing, as super knock can occur without the spark plug ever firing.
This video will describe the differences between light knock and super knock, how cylinder pressure is affected by each, how tuning can be used to avoid LSPI, and how motor oil can also be used as a resource to reduce the likelihood of LSPI and subsequent knock occurrences.//Engineering Explained