OK as per my other thread about my bank 1 sensor 2 (downstream down by the cat) I couldn't remove it. Well combining PB blaster, a propane torch, and a breaker bar the thing was mine.

So, happy, I went to remove the grommet that covers where the wire plugs into the car, as per instructions in the Haynes manual. Well haynes sucks because after I remove the grommet I see not only a hole that looks too small to put the O2 sensor end into, but the wires just go on forever in there. I mean seriously how am I supposed to disconnect the old wire, and more importantly connect the new one?!

 

OK I got it and I'll post in case anybody has the problem in the future. I pulled on the wires for the sensor and in time came upon the connection housing where the o2 plugs into the existing plug. Since you have to unplug this and then plug in the new one you first want to yank all the plug connection out of the bottom of the car. This is very tricky, or at least it was for me. The only way I could do it was to shimmy a kitchen knife between the plug and the bottom of the car where the plug was laying, and then lever the plug up vertically and try and pull it through. It's actually harder than it sounds because the very heavy dampening material (I guess that's what it is) above the plug resists you.

Then I finalized undoing the O2 sensor and found that the one nissan gave me (yep I specified Bank 1 sensor 2), does not fit the socket that the original O2 sensor came out of, so back to the dealership tomorrow.