Clarification
I have done some learning the hard way on this one.
It is clear that "1" refers to the sensor before the catalytic converter and "2" refers to the sensor after the converter.
Where I ran into trouble was with the 1, 2, left, right, driver, passenger designation.
The ODBII scanner told me that my failed sensor was "Bank 2, Sensor 2". After searching this forum, I found out that "Bank 2" referred to the driver side. However, RockAuto.com (and other retailers) doesn't sell sensors with the descriptors "Bank" or "Driver", instead they use left or right.
I was incorrectly told that left or right was determined if standing in front of the engine facing the car when in fact it should be if you are actually sitting in the driver's seat.
Long story short.........
BANK 1=PASSENGER SIDE=RIGHT
BANK 2=DRIVERS SIDE=LEFT
........at least in a 2004 V6 T4R.
One last tidbit, Bank 1 has a hell of a lot more real estate to work with than Bank 2.
I hope this helps someone out there......:violin: