i have a 1990 civic std hatch with a D15B1.
i replaced my stock header with a high performance header.
when i took the old header off it had the O2 sensor in it, but the wire was cut.
Where does that O2 sensor wire connect to?
i'd like to put a new sensor in, but i have no idea where to plug in the connector.
any help would be greatly appreciated. thanks.

 

I'll take a picture for you later tonight when I get home. It's really easy to find. If you look on the front of the trans you'll see I believe 4 plugs. 1 goes into the side of the head right under the dizzy, the other 2 go right into each other(really hard not to notice this) and the other is your 02 sensor.