Tip - How Do I Change a Knock Sensor in a Ford 5.4L? | eHow

A knock sensor is a piezometric crystal that advances or retards the engine based on load. Knock sensors are typically located on the intake side of the Ford 5.4-liter engine. All knock sensors connect to an electrical wiring harness and links to the vehicle’s On Board Computer (OBC). A knock sensors fails like a light bulb fails – it...