Strange problem with o2 sensor

INFORMATION Integra Help
1

I did a search on o2 sensors, but i’ve come up with a weird problem in my car.

Specs:

91 b16a

not two o2 sensors, but ONE 4 wire o2 sensor

91 ECU

is there something wrong with this picture, and could it attribute to my recent smog problem? What would i do to remedy it? TIA

2

ttt