Removal and installation of the exhaust system 4.4L (Discovery 3)

Special tool

Heated Oxygen Sensor Key 310-121 (LRT-19-014)

Removal

1. Disconnect the ground cable from the battery. For more information, refer to Specification.

2.

CAUTION: Never work on a vehicle supported only by a jack. Always support the vehicle with special stands.

Raise and support the vehicle.

3. Remove the engine protection. For more information, refer to Engine Protection (76.10.50)

4. Remove the transmission crossmember. For more information, refer to Transmission Crossmember (76.10.09 or 76.10.92)

5. Disconnect the left front heated oxygen sensor wiring harness. Disconnect the electrical connector.



6. Disconnect the right front heated oxygen sensor wiring harness. Disconnect the electrical connector.





7. Disconnect the left rear heated oxygen sensor wiring harness. Disconnect the electrical connector.

8. Disconnect the right rear heated oxygen sensor wiring harness. Disconnect the electrical connector.



9. Disconnect the left catalytic converter from the exhaust manifold. Remove and discard the 2 bolts.



10. Disconnect the right catalytic converter from the exhaust manifold. Remove and discard the 2 bolts.





11. Remove the exhaust system with assistance. Disconnect the 5 exhaust pipe fasteners.



12.

NOTE: Do not perform further disassembly if the part is removed only for access.

Using the special tool, remove the four heated oxygen sensors from the catalytic converters.

Installation

1.

CAUTION: Avoid contact of anti-seize compound with the tip of the heated oxygen sensor.

Using the special tool, install the heated oxygen sensors onto the catalytic converters and tighten (tightening torque 45 Nm).

• Clean the parts.
• Apply anti-seize compound to the threaded portion of the heated oxygen sensor.

2. Install the exhaust system with assistance. Attach the exhaust pipe brackets.

3. Connect the right catalytic converter to the exhaust manifold.

• Clean the parts.
• Tighten the new bolts. (tightening torque 22 Nm)

4.

CAUTION: Make sure that the distance (A) between the nearest surfaces of the left catalytic converter and the front drive shaft is 25-30 mm.

Connect the left catalytic converter to the exhaust manifold.

• Clean the parts.
• Tighten the new bolts. (tightening torque 22 Nm).

5.

CAUTION: Make sure the heated oxygen sensor wiring harness does not have bends greater than 180 degrees and does not touch the exhaust manifold or drive shaft.

[The article was copied from this resource www.lrman.ru]

Connect the heated oxygen sensor electrical connectors. Connect the heated oxygen sensor wiring harness.

6. Install the transmission crossmember. For more information, refer to Transmission Support Crossmember (76.10.09 or 76.10.92)



7. Install the engine protection. For more information, refer to Engine Protection (76.10.50)

8. Connect the ground cable to the battery. For more information, refer to Specification.