I have a 92 Civic Hatch with a D16Y8, the previous owner didnt connect the green/black wire and left it loose. Where does it plug into?

THANKS!!!

 

Its the ecu o2 sensor input ground wire.

 

So could I just ground it anywhere or does it need to plug into a certain place?

 

It does not have to be grounded unless you are using a 4-wire o2 sensor.

yellow/black=heater ground
orange/black=heater 12v +
white= o2 signal
green/black=o2 signal ground

This is all I could find this late at night.
http://hondata.com/techwidebandtuning.html