Knock Sensor: Testing and Inspection

- Warm-up engine to normal operating temperature.
- Attach a timing light with advance indicator and a tachometer.
- Locate the Knock Control Sensor, (on the RH side of the engine block), and ensure that the connector is secure.

Tachometer Hookup:

- While operating the engine at 2,000 rpm, check the ignition spark advance and calibrate the timing light to read 0° TDC.

Ignition Timing Marks:

- Using a wrench or small hammer, tap the exhaust manifold and observe the timing marks.
- The ignition timing mark should move in the retard direction, depending on the intensity and speed of the tapping.
- If the timing mark does not retard, turn the engine off and check the wiring between the Knock Control Sensor and the ECU.
- If no problems are found, replace the Knock Control Sensor and repeat test procedure.
- If timing still does not retard, replace the ECU.
- Disconnect timing light and tachometer from the engine.