B20b help

[92nyb20beg]

I have a 1992 Civic Dx with a b20bswap I just got the car and have been looking over things and the 02 sensor is not plugged in idk where it is and even if it is 4 or 1 wire I could use some help thanks

 

[Xanatos]

are you talking about the sensor on the car or on the wire harness? is it throwing a check engine light?