Replacing Rear O2 Sensor - New Wiring Harness or Cut/Splice?

[Ron Burgundy]

Yeah pretty much that.


I'm going to replace my rear heated O2 sensor. I just wasn't sure if I should go about replacing the entire wiring harness or just splice the new sensor into the old harness.

Thanks for the help!

[Razi]

Isn't there a part on the harness that disconnects near the O2 sensor?

[Ron Burgundy]

From what I've read, on a lot of vehicles it appears to be that way. But not on the Pathfinder. It runs from near the cat, through some pretty tight spots and into the engine bay.

[Towncivilian]

If there's an Advance Auto Parts near you, you can get a direct-fit sensor for around $50 after discount code if you order online and pick up in store. Which side sensor do you need?

The potential issue with splicing in a sensor is that how well you do the splice determines the durability of the connection. You also can't solder oxygen sensor wires since they "breathe" through the wiring, AFAIK. It is definitely a pain to remove all of the clips that secure the oxygen sensor harness, though - it definitely wasn't fun when I replaced my driver's side rear O2 sensor.

[Ron Burgundy]

I don't have an Advance Auto Parts nearby, do you know off the top of your head if they ship? Also, I thought I remember you mentioning Rock Auto carrying the same one?

Anyway, yeah I've read what about not soldering them as well. However, nearly every "how to" out there is always cut and splice. It seems to me like it would be better to just replace the whole thing. BUT with that being said, if it's really not gonna make a difference, the time I would save would be nice.

EDIT: Oh and I am replacing Bank 1, Sensor 2.

[Towncivilian]

AAP does ship, yes. Their site is a little strange in that they list 6 different oxygen sensors for a 2000 Pathfinder, that's why I asked which side you needed so I could find out.

RockAuto sells them as well, but you'd get it cheaper from AAP. Bosch is OEM manufacturer, at least on my 2001.5. It should say Bosch somewhere on the sensor, I was able to read one of them while it was still on the vehicle.

Cutting and splicing is cheaper, but I wonder of the connection's durability after some period of time. Also, usually the cut and splice O2 sensors are from some lesser known brands such as Standard Motor Products, etc.

EDIT: RockAuto is cheaper after shipping than AAP. This sensor is the correct one. Be sure to use a 5% off discount code.

[Ron Burgundy]

Yeah I think I'm with you there on the quality of cutting/splicing. You replaced these right? I remember your thread. Could you put in your $0.02 on replacing the full wiring harness.

Also, on AAP, the two rear O2 sensors are $85 and $95.

On Rock Auto, the same two are $65 and $72.

Which brings me to my next quick question, Bank 1, Sensor 2 - That's drivers side, right near the cat right?

EDIT: Beat me to it!
EDIT #2: Scratch that... Found it. Bank 1 - Passenger side.

[Towncivilian]

Bank 1 is always the side with cylinder #1. In the case of VG33E as well as VQ35DE equipped Pathfinders / QX4s, bank 1 is the passenger side.

I did replace my driver's side post-cat sensor. Read my experience here.