My car was pulling a rear heated O2 sensore code. Whie it was in the shop for another problem, they replaced the O2 sensor. About three weeks later I got the same code. Nissan said it is just a general code and the other sensor is dead. Am I being told the truth or a lie?

How am I supposed to figure out which one to replace, since I will be doing it my self this time?

 

Which O2 sensor did they replace? If you got the 0707 code, they should have replaced the sensor at the back end of the catalytic convertor.

An 0707 code can be caused by things other than a dead sensor. The code is thrown whenever the sensor produces a voltage signal other than what the ecu expects of it. This can be caused by such things as an air leak in the exhaust system upstream of the sensor, or a non-functioning catalytic convertor (e.g. a test pipe instead of a cat).

 

The sheet says they tested this sensor, O2S1B2, and there was 0 voltage. When I asked which sensor they replaced, they said they didn't know. When I brought it back in, they hooked it back up and told me the other sensor is dead.

 

Hmmm. And this is a Nissan dealership you're taking your car to? What code were you getting to begin with?

 

I don't remember the number, but it came up as "rear heated O2 sensor"

 

the rear heated one is the one in your catalitic converter. if you pull your own codes, maybe we can help you save some money. check here on how to pull a code. http://vbxmaxima.8m.com/ecu.html

 

Rear heated O2 sensor refers to the sensor in the cat, and a problem with it would have triggered 0707. If there was a problem with the front O2 sensors, it would have been worded to indicate front left or front right heated O2 sensor.

What I find strange is that if they replaced the O2 sensor in the cat, why are they now talking about "the other sensor"? There are two other ones (the front O2 sensors), not just one other sensor. That leads me to believe they are focusing on the front O2 sensors and mistakenly (or otherwise) changed one of them instead of the rear sensor. Maybe they think "rear heated O2 sensor" refers to the front right O2 sensor (i.e. the rear bank sensor)

And now they can't tell you which one they changed????

 

Yeah they are stupid, not keeping track of which sensor it is. I got the code by using that website. I asked if it was possible that they changed the wrong one and the guy instantly snapped that it was not possible.

 

Technician infallibility, eh?

They charged you for something that didn't fix the problem and now they can't tell you which one they replaced? I'd talk to the service manager or go higher.

Take a look under your car and inspect the sensor in your cat. I would think you can determine if that is the one they did or did not replace.

 

tell them to look at the heads of the o2 sensors, and you can almost guarenteen which one they replaced. theyve got to have recipts for the o2 sensor, so demand that you get one for it.

 

I found the printout of the sensor I need. It says "O2 sensor 2 bank 1" part number 22690-40u62. So, what should I order? and where would it go? I was thinking of ordering one from this site

 

That really sounds like they replaced the sensor for the rear bank (that is bank 1, I believe). If you are getting code 0707, which is "rear heated oxygen sensor", then they replaced the wrong one. They probably got confused by the wording. In this case "rear" means after the cat and they mistakenly took it to mean rear bank.

The rear sensor is also referred to as the downstream sensor in the website you reference.

 

yea tell thoes stupid idiots to replace it asap, and tell them no money is comming out of your pocket

 

Isn't the front right o2 sensor near the radiator/front of the car? I got a code for front right o2 sensor and I took out both just to be sure. The one near the front of the car had a white coating while the other front o2 sensor near the firewall was clean. What does this white coating mean? I replaced it and reset the ecu now my gas mileage almost doubled

I bought mine off of oxygensensors.com. I got the Walker OEM replacement it comes with ties and anti seize. After 700 miles no problems.

 

^^^ yea i have a code for front right heated 02 sensor. Which part of the y-pipe is that on?

 

front left is the one closest to the front bumper, front right is the next one down the pipe, and rear heated one is the one in the Cat (95-96) or b-pipe (97-99)

 

Now all of a sudden, the CEL light went off. It went off two days ago and has stayed off. Why would it do that, if I didn't reset the light?