Oxygen Sensors After Catalytic Converter

Oxygen Sensors after Catalytic Converter

Special tools, testers and auxiliary items required

• Ring Spanner 7-piece Set (3337)





• High temperature paste G 052 112 A3

Removing left oxygen sensor behind catalytic converter

- Remove rear engine cover (arrows).





- Remove cover - 1 - in engine compartment (left side).





- Remove coolant reservoir (arrow)





- Disconnect electrical wiring to Engine Coolant Level (ECL) Warning Switch (F66) at bottom of expansion tank.

- Tie coolant expansion tank with connected coolant hoses -1 to 3- to side.

Vehicles with automatic transmission

- Disconnect vacuum hose to brake booster (arrows).





All

- Remove heat shield for harness connectors at left of bulkhead, if installed.

- Remove harness connectors - 1 - to - 4 - from bracket at left of bulkhead.





- Disconnect electrical harness connector - 1 -.

- Move wire to oxygen sensor clear.

- Remove oxygen sensor behind catalytic converter (arrow) using special tool (3337/7).





• Illustration is shown with engine removed.

Removing right oxygen sensor behind catalytic converter

- Remove rear engine cover (arrows).





- Remove cover - 1 - in engine compartment (right side).





- Remove bolts (arrows).





- Disconnect Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) - 1 - at air guide.

- Remove air guide - 2 -.

- Remove air filter housing (arrows).





- Remove bolts for holding plate - 3 - for solenoid valves (arrows).





- Disconnect electrical harness connector at Mass Air Flow (MAF) sensor.

- Remove hose - 4 - of crankshaft housing ventilation from air guide - 2 -.

- Remove bolt (arrow) and disconnect air guide - 2 - at throttle valve control module.





- Disconnect hose - 1 - from air guide.

• Illustration depicts air guide with the removed engine from rear.

- Remove harness connectors - 1 - to - 4 - from bracket at right of bulkhead.





- Disconnect electrical harness connector - 3 -.

- Move wire to oxygen sensor clear.

- Remove oxygen sensor behind catalytic converter (arrow) using special tool (3337/7).





• Illustration is shown with engine removed.

Installing

Installation is reverse of removal, noting the following:

• Oxygen sensor threads are coated with an assembly paste. This paste must not be allowed to enter the sensor openings.

• Cable ties must always be installed again in exactly the same place to prevent the sensor wire from contacting the exhaust pipe.

• Tightening torque: 55 Nm