The knock control system is designed to reduce spark knock by detecting abnormal engine vibration through a knock sensor, which produces a voltage output that is monitored by the PCM. The system retards ignition timing until the detonation ceases, allowing for optimal spark advance and improved driveability. To check a knock sensor, disconnect the electrical connector and use an ohmmeter to check for continuity between the knock sensor terminal and the body of the sensor. If continuity exists, replace the sensor. To replace the knock sensor, disconnect the battery cable, drain the cooling system, remove the intake manifold on V6 models, disconnect the electrical connector, and remove the sensor. When installing a new or reused sensor, ensure it is securely tightened (approximately 30 ft-lbs) and the threads are coated with thread sealant as necessary. Refill the cooling system and check for leaks.