Method and system for reducing engine knock in an internal combustion engine

摘要

A system for reducing knock in an internal combustion engine is disclosed and includes a vibration detector which detects engine vibration and generates an output signal representative of the magnitude of the engine vibration over a predetermined frequency spectrum. The vibration output signal multiplied by a first weight factor is integrated over a lower portion of the frequency spectrum to obtain a first value while the vibration signal multiplied by a second weight factor is integrated over a higher portion of the frequency spectrum to obtain a second value. The first value is compared with a first threshold value and, when the first value exceeds the first threshold, the system generates a fuel control output signal to increase the fuel supplied to the engine to reduce engine knock. Similarly, the second value is compared to a second threshold value and when the second value exceeds the second threshold value, the system generates a spark ignition control output signal to retard the engine spark ignition thereby reducing engine knock.