I have to replace oxygen sensor bank 2 sensor 2. Is this a hard job? It seems like it is without knowing. Though I thought it was going to be an easy job.

The oxygen sensor that I got sent to me is the same size and width as what you see in the first most left plug in the engine picture. As you know it will not fit because it is the exact same thing if you can understand what I am saying. I will include a stock picture of it. Also the oxygen sensor wire seems too short and does not look as long as the one in the picture. Not sure if that will actually make a difference in the final outcome.

Also I am including a picture of the oxygen sensor socket that I got. The one that seems like it will not fit on the pictured oxygen sensor because of being too cramped.






I am including pictures all with text on them because I think it will just be easier I feel:

 

Likely all you need to know …

http://boredmder.com/FSMs/Nissan/Maxima/2003/

 

when I remove an oxygen sensor I always cut the wires and remove them with a regular 6 point socket.

when I install them, I just tighten them as much as I can with an open end wrench.

 

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While that just might be good information, I do not think it can help me in my situation as I need some hands on, specific, interactive help that would actually help me. That is why I included visuals and text explanations for decisive help and answers.

 

I do not think that can help me out in what I am needing currently. Plus I cannot cut wires I am not sure what they are exactly. Huge detrimental risk.

 

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uptown, bro, can you possibly help me out in identifying the things in the pictures I have shared, since you have or had this car as you stated you were doing major engine work to this vehicle previously. I desperately need the help and guidance with and from those pictures and text references I shared.

 

https://maxima.org/forums/5th-genera...2-sensors.html

Reference with this thread. Once you positively ID the correct sensor you can cut those wires and use a regular socket. I wouldnt attempt an open wrench because typically o2 sensors are stuck af and youll probably just strip it. Make sure to use a proper penetrant like PB Blaster (not wd40) and this will make it infinitely easier, especially if you let it soak in for a while.

 

I have saw those pictures and that video but nothing shows the wire to the plug.

 

Just follow the wire lol. Or look at the factory service manual, learn it, love it - it has *everything* in it.
http://boredmder.com/FSMs/Nissan/Maxima/2000/EC.pdf



For 02-03, and 00-01. For your purposes o2 harness layout is identical.

 

Your side note question about the unplugged grey connector on the battery side of the engine bay. May have once been connected to an electronic motor mount underneath the front of the engine. If so, leave it alone, those are known to cause issues with the electronics.

 

I think that loose connector is for the original radiator fans, there should be 2 fans. Do you only have one fan?
Yes those are converters.
That O2 sensor is in a tight spot. Cutting the wires and using a closed end 22mm wrench is your best bet. Otherwise take the catalytic converter off the car. On your car the upstream O2 (before the cat. con.) are 3 wire. Downstream O2 (after cat) are 4 wire.

 

Huh … imagine that.

 

you can use a 7/8 wrench to remove the o2 sensor. just make sure to keep spraying it with pb blaster over a few hours. also, if it won't bulge try tightening the loosen..tighten then loosen until it will break free.
if you follow the wire from the sensor you can unplug it so you do not damage the wires while removing and installing.

 

Hi. In the two pictures I address asking if they are or if I have the catalytic converter, are those it? As stated previously, I do not want to cut any wires because I would be risking cutting something I need, I have not performed oxygen sensor removal ever that is why I am trying to get all the information I can. I guess I just do better understanding visually and hands on. Most of my exhaust and I know a catalytic converter is already gone, going towards the muffler. They fell off one day from being rusted.

 

Thanks. I do have an alternate fan in there, a big solo round one, not the square duals that came originally. I will explore that little plug more but probably a non-issue and concern. Oh and thanks about the converters... I guess I still have two? I thought when my exhaust and pipe with the converter had fallen off from rust they were all gone. I will explore more and maybe remove them to try to gain more access. Should I just return this oxygen sensor socket and just use the open wrench as others are suggesting? I have to get one that big, I bought a wrench set recently but the biggest one would not fit the oxygen sensor. I bought it for different purposes. But I guess I have to get a singular bigger one to fit the oxygen sensor. That current oxygen sensor socket will not fit the socket because of how cramped it is as I stated but maybe if I take that converter off I will have more access? I just have to get under there again and do some more exploring as well. Also I was visually trying to find the bank 2 sensor 2 specific wire and follow it to the plug when I was unsuccessful my first attempt.

 

Thank you for those pictures. I have attempted looking at the manual previously for a different reason and it all just seemed a bit overwhelming to me trying to take it all in. I was just trying to pinpoint currently my current issue with some good visuals and hands-on information I suppose. I am going to study those two pictures you shared further.

 

I have an 02 with a 6 speed, not sure how different the wiring is but on the 02 and 03 the O2 sensor wires are pretty easy to follow when looking from under the car, just change them one at a time and unclip the wire from it's attachment points to make it easier to figure it out. if you remove the radiator fan you will have a better view of how the wiring is routed.

I know the oblong connector with the wires in a row is the upstream or main O2 sensor connector and the square ones are secondary but I'm not sure which is which since my ECU is flashed and I don't run them anymore. just do them one at a time so you don't mix them up, that's the easiest way to do it once you remove the sensor.

as for the sensor itself do not use a wrench for removal you will round out the hew on the sensor. I always use a 6 point 7/8 impact socket for removal and an open end of a 7/8 wrench to install them. they don't have to be super tight just good and snug so the seal doesn't leak which is why the open end of the wrench is good enough for installation.

 

I feel like there is some confusion here about the catalytic converters in general...

Yes, there are THREE total converters.
There is an O2 sensor before and after converters 1 and 2 (in the picture below) for a total of FOUR O2 sensors.

The sensor BEFORE the converter can be called (sensor 1) or (front)
The sensor AFTER the converter is called (sensor 2) or (rear)

Bank 1 is closest to the firewall, Bank 2 is toward the front of the car.

The drawing below does not show the Bank 2 front sensor, because it is included on the engine drawing, and NOT on the exhaust drawing.

From your earlier pictures and your comments, I'm thinking that if converter #3 FELL OFF and is currently missing, this might be priority no. 1 to replace.
Secondly, hopefully you removed the three bolts that are missing in your picture (notated with yellow Xs below) in an effort to get to the 02 sensor, but if not, this would be bad if they're missing.
You would not want to sit still in this car with the engine running for any length of time.

 

the O2 sensors will also be referred to as upstream or downstream. upstream before the cats that measure the air fuel ratio and downstream after the cats to monitor emissions.