2017 Infiniti G37 Sedan V6-3.7L Diagnostic and Repair Information # 10-008 Date: 100119
Engine Controls - Seized O2 Sensor Removal Procedure
Classification:
Page 217
EM09-016
Reference:
ITB10-008
Date:
January 19, 2010
REMOVAL PROCEDURE FOR SEIZED EXHAUST SENSOR
APPLIED VEHICLES:
All Infiniti vehicles
SERVICE INFORMATION
If an exhaust sensor is seized in the exhaust manifold/catalyst/front tube perform the procedure described in this bulletin to remove the sensor and
prevent unnecessary replacement of the exhaust manifold/catalyst/front tube.
In most cases this procedure is successful. This is because the threads of the exhaust sensors are made of a softer material than the part they thread
into on the exhaust manifold/catalyst/front tube.
NOTE:
The replacement of exhaust manifolds/catalysts/front tubes for stripped exhaust sensor threads may not be considered a warrantable expense.
This procedure can be performed by two methods:
Method # 1. If the Sensor Can Be Easily Accessed
^ The procedure can be performed on the vehicle.
^ The exhaust manifold/catalyst/front tube will not have to be removed.
Method # 2. If the Sensor Cannot Be Easily Accessed
^ The exhaust manifold/catalyst/front tube must be removed from the vehicle.
^ The procedure will be performed with the part clamped in a vice.
Method # 2 is described in this bulletin. Method # 1 is the same as Method # 2 except that it is performed on the vehicle.
SERVICE PROCEDURE
Rust Penetrant
Recommended rust penetrants to be used in this procedure:
NOTES:
^ Rust penetrant is considered a shop supply.
^ Nissan Rust Penetrant can be ordered through the Nissan Direct Ship Chemical Care Product Program: Website order via link on dealer
portal.
^ WD-40 is available from various local sources.
Removal Tool
^ When removing a seized exhaust sensor with a specialty socket (which contains a slit to accommodate the wiring harness) it may spread open
and strip the sensor.
^ Before this occurs it is recommended to cut the wiring harness from the sensor and use a box end wrench or 6-point deep well socket.
1. Clamp the exhaust manifold/catalyst/front tube in a vice.
Page 218
2. Spray the sensor with the rust penetrant for 2 to 3 seconds.
^ It is important that the spray is directed at the base of the sensor to ensure it penetrates into the threads.
3. Loosen the sensor approximately 10 degrees.
4. Spray with rust penetrant again for 2 to 3 seconds.
5. Tighten the sensor 10 degrees then loosen the sensor 10 degrees.
^ Repeat this motion several times until the sensor begins to turn more easily.
6. Continue the tightening/loosening motion while gradually unscrewing the sensor. Stop when the sensor will not unscrew any further.
7. Spray with rust penetrant again for 2 to 3 seconds.
Page 219
8. Repeat steps 6 and 7 until the sensor is removed.
9. Use compressed air to remove any metal debris from inside the boss threads.
CAUTION:
DO NOT perform this step if the procedure is being done on the vehicle (Method # 1). Doing so may cause metal debris to enter the engine
cylinders.
10. If metal debris remains trapped in the boss threads use a spiral nylon brush to remove it.
11. Spray the boss threads with rust penetrant for 2 to 3 seconds.
12. Run a thread chaser through the boss to clean the threads.
^Use Kent Moore part number J-43897-18 or J43897-12.
13. Use compressed air to remove any remaining debris.
CAUTION:
DO NOT perform this step if the procedure is being done on the vehicle (Method # 1). Doing so may cause metal debris to enter the engine
cylinders.
14. If metal debris remains trapped in the boss threads use a spiral nylon brush to remove it.
15. Tilt the manifold/catalyst/front tube so that the metal debris falls out of the part.
16. Apply compressed air through the boss to blow out any remaining debris.
Page 220
CAUTION:
DO NOT perform this step if the procedure is being done on the vehicle (Method # 1 ). Doing so may cause metal debris to enter the
engine cylinders.
17. Install the new sensor as described in the applicable Electronic Service Manual (ESM).
