I've been running my car with SES light for a while and I found out it's P0138 Heated Oxygen Sensor (H02S) Circuit High Voltage Bank 1 Sensor 2. Can anyone tell me where that sensor is located . Pics of where it is would be very helpful or any kind of info. Thanks guys.

 

bank 1 - rear manifold, sensor 2 - secondary o2. If you look underneath the valve cover on the front of your car after the radiator there are four plugs. The P0138 is the plug with the white harness. Follow that down to your o2 and you've got it

 

On my 02 Max there's no white harness. I see those four harnesses under the cover, but none of those are white, only one harness has white wire though. Perhaps on your 01 Max it's different.

 

could you name the harness colors? i've worked on 2k2s and they are the same as mine

 

Here are the harness colors of the sensors.

 

I think he meant the one with the white wire covering. I had a code p0140 and the stealership told me it would cost 540 to replace two sensors, the white wire and the red wire one. I did the parts myself and brought it to them for the ecu reburn. Total cost for me 280.

 

You mean you installed the parts by yourself, and $280 for the ecu reburn?

 

the parts were 210 and the reburn was 70.I got the parts from autozone. the dealer wanted 180 a piece for each o2 sensor.

 

Man $70 bucks for the reburn. So do you have to reburn the ECU after you change the o2 sensor???
By the way did autozone had the sensors in stock or they had to order? cause our autozones doesn't have them and they could order $137 a piece.

 

yeah that was their hourly labor charge.All they do is hook it up to the machine and take a coffee break. You could get lucky and change the sensor and reset the ses light if you have a scan tool.Nissan has a tsb out for my particular code, can't remember if yours applies too. I've had so many problems with the car I just wanted them to do reburn it so that if the ses was still on I could have b*tched them out about it. I did have to order the sensors. One was 90 and the other was 110 + 5% tax. It took about a week for the parts to come in. Just make sure you check they are the right ones cause the first time they one of the sensors I got was the wrong one. Three days later I got the right one and everything was fine after that.

 

The link for the tsb is http://maxima.theowensfamily.com/tsb/NTB02-051a.pdf

 

Thanks that might be helpful.

 

I have the same code right now as you, I got the sensors (I own an auto parts store so I got the 2 Bosch replacements which are the same as OE), but I wasn't going to do the ecu update, I was just gonna clear the CEL with my scan tool and be done with it, anyone know how important it is to reflash the ECU after replacing the sensors?

 

sorry not to steal this thread, but thats my problem Im not an forum idiot but I cannot start a new thread. The message tells me I dont have the privalege.

just wondering why I cant

Thanks in advance...

 

buy an universal O2 sensor , I did and it worked just fine for me !!!

 

I am not sure if you have to "re-burn" your cpu on 02+. Anyone know for sure?
And why are 02 sensors so damn expensive??

 

Ya need 15 posts.... http://forums.maxima.org/announcement.php?f=10

 

Don't quote me on it, but I think in the past people have just swapped out O2 sensors, done the ECU reset procedure, and things have been fine... I THINK...

I'm sure someone with more technical expertise could verify this....

 

Larrio so the P0138 o2 sensor is the blue harness with white wire, right?

 

yesterday when looking at the org i noticed there was a post about gas mileage and i have a 2000 max gle and i only drive city miles and from full to light turning on i was wondering how many miles i should get want to see if there is something wrong with the way i drive or something else

 

yes

left to right
1: blue harness/ light blue plug - primary front bank (bank 2)
2: red harness/ green plug - secondary front bank (bank 2)
3: white harness/ dark blue plug - secondary rear bank (bank 1)

 

Shoot I think I might have a problem with mine as well and if it is the blue one then that is hella close and fairly easy to get to.

 

Yeah stay below the 3000rpm and then see how many you'll get. Don't floor the pedal. By the way do you have SES light on, or not? If not then I guess slow down bro.

 

Ok thanks a lot bro, then I'll try to get that one. I think it's like $137, kinda a lot.

 

And to add an FYI to what Larrio posted... this TSB:

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

It has diagrams of where all the O2 sensors are, bookmark or download it... its useful to have...

 

also check this thread it may be helpful http://forums.maxima.org/showthread.php?t=405138
Oh, aren't you under warranty being your car is an 02

 

yup thats true i did that and my car has been just fine

 

yeah i got the same code guys for p0138. i want to replace mine as well but i read that link from above and it says that both rear bank 1 and bank 2 should be replaced. or is it okay to change only one? and bank 1 is the blue connector and bank 2 is the green conector to the left of the blue connector right? how much are they each and if i buy them from nissan, are they going to fail on me again? thanks guys.

 

I think you need only one. I hope they will not fail us agian, cause I'm researching about these sensors before I get one. So far I'm going with OE type Walker. I think those are good.

 

I just ordered one from Dave B. It comes with the connector and everything so no splicing!! Hopefully it won't be too much of a pain to replace.

 

how much did you pay for it?

 

It was $108 shipped. And you do have to specify which one you need.

 

i just put the o2 sim in mine because the secondary one kept blowing up everytime I did a hard run (2nd and 3rd gear redline)

it was another excuse to convert to fed-spec also

 

I have to replace mine also and can not figure out the routing. I see it in the engine compartment and I see it where it plugs in on the exhaust pipe. From the exhaust pipe, it goes up thru the drivers side floor board. From that point, I can not tell how it routes. Can someone give me guidance? Do I have to remove carpet, etc.?
Thanks

 

I had the p0140 and just replaced the white one I got the sensor for 60 and just installed it myself and then I had my friend do the ECU reprog and gave him a case of beer and all was good

 

Is it really necessary for a reprogram when you're replacing a faulty sensor? I think you can just plug and drive.

 

It's not really necesary, but you'll be getting CELs more often due to "too narrow" response parameters.

 

There's a TSB out there that calls for a reprogram if you pull certain o2 codes.

 

Hey guys, my friend has a 99.5 cali-spec I30 which has the exact 02 sensor layout as the 2000+ cali-spec Maximas. His car recently threw the P0138 code. My OBDII scanner said Bank 1, sensor 2. My question is exactly which sensor is this? Is it the sensor down at the Y-pipe junction right next to the crossmember (faces towards the front of the car, technically mounted downstream of the rear precat).

 

^^^ Yep, that's it.