2000 max, fed spec. I have replaced a rear O2 sensor before and it's straight forward. I need to do my Bank 1, Sensor 1 now, which is at the front of the car, rear of the engine, I believe on the passenger side. I've looked at a diagram of the engine bay, spent a good bit of time under the engine but I cannot even SEE the O2 sensor to get to it. Last time I tried to replace it I think I MIGHT have been able to find part of the wire harness, but how can I get at this? Does anybody have a good pic or idea? Thanks!

 

Answers to your questions is posted in the FAQ

 

http://maxima.theowensfamily.com/tsb/NTB02-051a.pdf

Pay attention to the pretty diagrams in that link.

 

I did look in the FAQ but it links only to the drawn diagram of the O2 sensor, which I've seen before--I really need a bona fide picture to the darn thing!

Thanks for the PDF link, but that file is bad; it doesn't open with any actual content!

 

It opened fine for me. Make sure you have an updated version of Adobe reader.

 

It is sort of on the passenger side behind and below the intake manifold, on the rear exhaust manifold. You can either get to it from above or from below, but it is hard to see. You can either remove the IM (at least, for the VQ35 this works) to see if it'll give you more clearance and a visual or you can remove the subframe cross brace with the front and rear motor mounts to access it from below. Or do both, if you want. Now that I think about it more, it was easier getting to it from the bottom. With the subframe brace off, you can tilt the motor back to gain access to it, but it is still in a tight spot.

 

only if there was another thread on this.Red box is cali spec.

 

I got that pdf to dl but can only open the first two pages. I bet it's my adobe; I'll try it again when I get home

So based on the above, I have to detach other things like engine mount to propertly get this one?

 

you shouldnt, when i put on my y pipe i was able to get all of the O2 sensors off the stock y pipe with it still fully attached to the car

 

OK I found the sensor. I remember what the problem was last year--in fact, the sensor is easy to find and not to bad to get at. It's the wire harness that is the problem--I have a spare sensor and the wire doesn't look long, but I cannot see for the live of me where the wire runs to and where I need to plug/unplug; following the wire just goes up into the engine bay somewhere and I'm left wondering where the heck the end is. Where is the other end of it and how can I unplug the old sensor?

 

comes plugged into 1 of the 4 DIFFERENT coloured plugs sitting looking at you when you open the hood kinda like on top of the dipstick but lower than the engine cover. That harness goes all the way to the back by the firewall.

 

Yep, that's it

I have replaced it. I was unable to properly hook one of the wire hooks near the top to something but got the bottom one so it should be fine. Definetly tight confines in there. It was easier that the axle was out but I doubt that really matters too much.