Spark timing control system for an internal combustion engine

摘要

An ignition spark timing control system for an internal combustion engine capable of controlling the ignition spark advance angle corresponding to a knocking condition of the engine. The spark timing control system includes a means for retarding spark timing in response to an engine knocking condition and a means for detecting unstable driving condition of the engine and interrupting the retarding of the spark timing when the engine driving condition is unstable in order to maximize the engine output characteristics and improve fuel economy.