Circuit/System Description

The knock sensor (KS) system enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The ECM monitors 2 separate KS, located under the intake manifold. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM receives the KS signal through 2 isolated signal circuits and adjusts the spark timing based on the amplitude and frequency of the KS signal.