'04 Lexus SC430 Oxygen sensor replacement
'04 Lexus SC430 Oxygen sensor replacement
The PDF tells you which bank 1 sensor 1 is. Driver's side/Passenger side isn't a good way of working it out because yours is different to ours! Although your car has a 3UZ-FE engine which isn't directly listed, it WILL be the same as a 2UZ-FE.
I don't think the one right behind it is likely to fail because there is a catalytic converter inbetween them. Presuming they are talking about the same bank, sensor 2, rather than bank 2 sensor 1.
When I attempted to replace the sensor, I apparently was not able to locate the upstream location of S1/B1 - The only sensor I located (just one on the left or right side) was right under the front seat floor pans, & I didn't see any other sensor location...? Those sensors have a longer wire assembly (10-12 inches) then what I was given as the S1/B1, which has a 6-8 inch wire. I'm not able to locate the upstream sensor. Help!