Ok I have searched my little heart out and I can't seem to find this answer. Plus my head hurts now.

I have my Service Engine Soon (SES) light on and I looked up the code: P0139 & P1147 (Bank 1 rear) so from this picture below



The sensor I need to replace is the 1st O2 sensor on the cat right? Also due to some $$ issue I currently have I was going to pick up a 3 wire Bosch O2 sensor. I can't seem to find a wire diagram that shows me what wire goes where. Any help would be great. Thank you in Advance.

 

Oh I forgot to tell you all that I have a 2002 Maxima SE. No mods this is my daily driver. Again any help would be great. Thank you

 

I'd recommend springing an extra few $ for the O2 sensor w/ the wire. The problem w/ the sensor could be a result of a wire issue. Plus you could have future connection issues. When I replaced mine I went w/ the wired version.

 

Cdoc's right, if it's not that great of a connection, you could get the code again.
I believe you need to replace the one that says *WHITE; bank 1 sensor 2

 

I had these same two codes in my 2K2 a few months back.

Using the diagram you attached, it is easy to find the sensor - it is the white one.

I used an OEM replacement sensor so I can't comment on the Bosch. You should be able to find an OEM O2 sensor for in the neighbourhood of $110.

I found the sensor to be pretty easy to replace myself. The biggest PIA by far for me was all of the little clips holding the wire in place. Another advantage of the OEM sensor is it comes with all of these little clips in place so that you can just rip the old ones out and not worry about it. This would be a much more difficult job if you had to worry about reusing the old clips.

There is a TSB out there which covers this O2 sensor failure (you should have come across that in your searches). It covers sensor replacement and a "reprogram" by the dealer. Not sure what your mileage is, but a few have had luck getting this repair done under the 80K emissions warranty. Most dealers will do the reprogram under the emissions warranty but will only replace the sensors under the 36K warranty. If you are the persuasive sort, you might want to approach your local dealer and see what they'll do for you.

If the dealer like they usually do, you can either fight it or bite the bullet and pay for the reprogram and replace the sensor yourself. A reprogram should cost you about 1 hour labour MAX.

Hope that helps.

 

Thanks guys, I will just get the OEM replacement as you guys recommand. Also I am a bit over 110,000 on my Maxima and still running strong. Other then this issue The car has been perfect!