Where is Oxygen sensor bank 2 sensor 1 in Cadillac DeVille?
It's between the engine and the fire wall. it's pre catalitic converter. There is very little room. It's best to see and work on from drivers side fender. Make sure the exahust is warm to help with removing the 02 sensor.
I believe 96- 04 have the same engine placement. Deville and Seville.
My Seville SLS is a 01 and has three o2 sensors. 2 pre cat and after.
to remove the one after the cat you have to drill out the rivets on the cover plate and then when you replace the cover you will have to use self taping screws!
I may be wrong but I tried my best to help you.