bank 1 sensor 2 oxygen sensor

[Engine5Lt]

Which O2 sensor is the bank1 sensor 2 on my 1997 S-10 2.2 4 cyl? The OBD said this was bad and it is missing on cylinders 1 and 4. I have already replaced the spark plugs and the coil for cylinders 1 and 4 with minimal improvement. It runs OK when cold but starts running poorly when warm. I need to know which sensor to replace first and there is a large difference in price between the 2.

[Engine5Lt]

OBD actually said random multiple misfires but the plugs from cylinders 1 and 4 were fouled out while the other 2 plugs looked OK

[Fireplug]

bank 1 is drivers side sensor 2 should be the 1 just before the cat ,sensor 1 should be on the exhaust manifold/y-pipe

[Engine5Lt]

Does anyone know if a bad O2 sensor or catalytic converter could cause the rough idle and misfires?

[Fireplug]

9 out of 10 times no on both. The o2 is telling you it has detected a problem. The o2 is not the problem, its is doing its job by seting a code. Check your fuel pressure, cloged injectors or leaking injectors

[fishing]

I have a sonoma 1996 4.3L and at one time had similar if not nearly identical codes. I replaced 2 of the O2 sensors...nothing.
finally a mechanic neighbor said they had a truck with the same codes and they sprayed the manifold air pressure wire (removed from throttle/intake assembly) with carb cleaner. I could see absolutely nothing on my wire (he said I wouldn't), truck ran fine and the codes never returned...