Knock Sensor: Service and Repair

Fig.22 Knock Sensor Location - 4.7L H.O.:

KNOCK SENSOR - 4.7L High-Output Engine Only
The 2 knock sensors are bolted into the cylinder block under the intake manifold.

NOTE: The left sensor is identified by an identification tag (LEFT). It is also identified by a larger bolt head. The Powertrain Control Module (PCM) must have and know the correct sensor left/right positions. Do not mix the sensor locations.

REMOVAL

Fig.23 Knock Sensor Elec. Connector - 4.7L H.O.:

1. Disconnect knock sensor dual pigtail harness connector from engine wiring harness connector. This connection is made near the right/rear of intake manifold.
2. Remove intake manifold. Refer to Engine section.
3. Remove sensor mounting bolts. Note foam strip on bolt threads. This foam is used only to retain the bolts to sensors for plant assembly. It is not used as a sealant. Do not apply any adhesive, sealant or thread locking compound to these bolts.
4. Remove sensors from engine.

INSTALLATION
1. Thoroughly clean knock sensor mounting holes.
2. Install sensors into cylinder block.

NOTE:
- Over or under tightening the sensor mounting bolts will affect knock sensor performance, possibly causing improper spark control. Always use the specified torque when installing the knock sensors. The torque for the knock senor bolt is relatively light for an 8 mm bolt.
- Note foam strip on bolt threads. This foam is used only to retain the bolts to sensors for plant assembly. It is not used as a sealant. Do not apply any adhesive, sealant or thread locking compound to these bolts.

3. Install and tighten mounting bolts. Bolt torque is critical. Refer to torque specification.
4. Install intake manifold. Refer to Engine section
5. Connect knock sensor pigtail wiring harness to engine wiring harness near right I rear of intake manifold.