Knock Sensor Replacement 5.0L,5.7L,7.4L

The knock sensor is located in areas of the cylinder head. On most applications, the knock sensors are installed in a hole which is exposed to engine coolant. Care should be exercised when servicing these sensors.

1. Disconnect the negative battery cable.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

Important: On knock sensors which are mounted in the end of the cylinder head draining the cooling system will not be necessary.

2. Drain the cooling system. Refer to Engine Cooling.
3. Remove the wiring harness connector from knock sensor.



4. Remove the knock sensor from cylinder head.

Important: Do not use silicon tape as this will insulate the sensor from the engine block.

1. After applying a water base caulk to the sensor threads, install the knock sensor into the cylinder head.

Tighten
Tighten to 19 N·m (14 lb ft).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

2. Connect the negative battery cable.
3. Refill cooling system if required. Refer to Engine Cooling.