fdjizm

ok first off i have a 98 lx with a 99 d16y8 engine in it, and i wired the stock harness for vtec.. so i bought a wiring harness off ebay (96-98 civic lx a/t)
i do have an ex harness but cant figure out how to wire the second o2 sensor, so i bought the lx harness and wired the vtec stuff, now big problem, at the end of the harness i bought there is one connector the big giant one that goes into the right side of the car.

now the wiring harness thats in my car has TWO connectors at the end of the harness one big one just like the other harness but next to it, theres a smaller one with 4 wires.. so why doesnt my harness have that extra connector if its indeed from a 96-98 civic lx auto.. (i know its obd2a just like my car pinouts the same). so what does this 4 wire huge connector do? i think it has to do with the tranny i disconnected it and couldnt shift out of park.. so what happend?