Possible Cause

NOTE:  The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

• Rear WU-TWC (bank 1) deterioration
• Rear secondary HO2S (bank 1, sensor 2) line electrical noise overlapped
• Rear secondary HO2S (bank 1, sensor 2) connector loose connection
• Exhaust system change (non-genuine part)