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Discussion Starter · #1 ·
Sup guys, how's it going? On my '07 2.3L, I got a p0138 error code for O2 Oxygen Sensor Circuit High (Bank1Sensor2). Kinda makes sense now cause my gas mileage was declining quite noticeably and I couldn't figure out why.



But before I order new ones I want to clarify some stuff. I see people saying to replace the sensors in pairs. Does that mean I order an upstream and downstream one and I'm set? Or are there more than two o2 sensors. Thanks a ton, sorry if it's a dumb question. I appreciate any help, cheers
 

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Curious to know how this goes. I just picked up a "new" 2007 after the rust on my 2005 at 260k became too much to bare. It threw this same CEL and I've read that it's a bitch to really iron out.

Have you done a freeze frame check or watched the data coming in from that sensor to make sure the issue really is the O2 sensor?

I have Torque Pro and set a gauge for that bank and the data flows fine. Though, our cars may never have had these sensors replaced so maybe replacing them is the right thing to do especially since, I'm told, it's a pretty dang easy repair.
 

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Discussion Starter · #4 ·
Curious to know how this goes. I just picked up a "new" 2007 after the rust on my 2005 at 260k became too much to bare. It threw this same CEL and I've read that it's a bitch to really iron out.

Have you done a freeze frame check or watched the data coming in from that sensor to make sure the issue really is the O2 sensor?

I have Torque Pro and set a gauge for that bank and the data flows fine. Though, our cars may never have had these sensors replaced so maybe replacing them is the right thing to do especially since, I'm told, it's a pretty dang easy repair.

Just saw this, sorry for the late reply. Yeah so around 2 months or so ago I was getting the CEL off and on, and noticed my mileage going down pretty significantly. I ordered a NTK downstream sensor from rockauto cause I heard they were better than the cheaper Bosch ones. Anyways I replaced it 2-3 weeks ago and it's been fine ever since, no CEL or any hassles on my end.



I probably should've checked to see if it really was the sensor causing the CEL first but I just kinda winged it. Sorry I can't help on that end, lemme know how it goes
 

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Sup guys, how's it going? On my '07 2.3L, I got a p0138 error code for O2 Oxygen Sensor Circuit High (Bank1Sensor2). Kinda makes sense now cause my gas mileage was declining quite noticeably and I couldn't figure out why.



But before I order new ones I want to clarify some stuff. I see people saying to replace the sensors in pairs. Does that mean I order an upstream and downstream one and I'm set? Or are there more than two o2 sensors. Thanks a ton, sorry if it's a dumb question. I appreciate any help, cheers
BUMP
I have the exact same car with the exact same issue. How did you end up fixing your P0138 code? Did you do it yourself?
I've been getting $800+ quotes from mechanics in my city and I don't have that cash lying around.
Cheers,
Mate
 
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