Detonation (knock), pre‑ignition, and LSPI are often conflated, yet they differ in timing, triggers, and severity. Detonation is end‑gas autoignition after the spark; pre‑ignition is any unintended ignition before the commanded spark; LSPI is a stochastic pre‑ignition mode peculiar to boosted, low‑speed, direct‑injection gasoline engines. Modern ECUs manage these with knock sensors, ion‑sensing, and closed‑loop timing and fueling. Understanding their mechanisms and the control toolbox explains why engines can run 9.5–11.0:1 compression with 1.2–1.8 bar absolute boost on 95 RON fuel while preserving durability and emissions.