P0037 Low bank 1, Sensor 2

glutengoblin

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Question: My 2003 4.0L Forerunner came up with a P0037 code, I replaced the drivers side 02 sensor after the catalytic converter. While replacing it I had the negative battery terminal disconnected...after driving for about 15 minutes, CEL light came back on and the same code came up.

-How long/how many drive cycles need to happen before this code should clear itself or should it have cleared itself immediately? What is a drive cycle for this vehicle?

-Would this CEL have any bearing on the VSC lights being on as well for the 4th gens?
 
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Are you sure you replaced the correct sensor? Pretty sure that code points to bank 1 sensor 2. That should be passenger side after cat O2 sensor. The VSC and trac lights come on with the CEL.
 
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Alright--you guy's nailed it. Replaced the passenger side 02 sensor and after a few drive cycles the light cleared itself. Thanks.
 
kosan...I would think that a faulty 02 sensor would result in catalytic converter damage rather than a faulty catalytic converter resulting in faulty 02 sensors...doesn't an 02 sensor impact the unburned oxygen that's passing through the catalytic converter?
 
The ECUs on these things are finicky as heck with emissions and cats.

Buy a bluetooth OBD2 scanner and download "Torque". Until it pulls multiple codes, clear it and go on.
 
kosan...I would think that a faulty 02 sensor would result in catalytic converter damage rather than a faulty catalytic converter resulting in faulty 02 sensors...doesn't an 02 sensor impact the unburned oxygen that's passing through the catalytic converter?

To clarify, when I started to get these codes, I tried the suggested comments on here with resetting using the obii scanner and replacing the gas cap since it was a cheap fix. Although it seemed to work, I couldn't tell as the code would pop up every 200-350 miles. Then, after a year or so, the error would pop up much quicker, every 75-100 miles or so. At that point, I just decided to change out the O2 sensors and see what happens. But unfortunately, luck was not on my side. So, I begrudgingly had to change 1 of the cc. Seemed to work for a little but after more research, it was expected that i would have to change the other cc soon as well. And, well, soon enough, I had to change the other cc!! haha. Emissions here is every 2 years so I took the long route of fixing this. haha. :reddance:

Anyways, as others have suggested, it could be a simple fix as resetting the codes or a gas cap but could be as pricey as replacing both cats. Good luck!
 
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So what to do if the error code keeps reoccurring?
(Check Engine, VSC and VSC Trac Off)

Replaced Bank 1 Sensor 2, cleaned all other sensor connectors, reset Zero Point Re-calibration - lights still come back on.

Help!!!

Thx in advance.
 
Just as a reference.

P0037 code - Bank 1 Sensor 2 on...

2004 V8 is on the DRIVER side downstream of cat. I know from screwing around for weeks with the passenger side and suspecting all sorts of other problems.

Soon as I changed the driver, cleared the code, did a zero point calibration the problem was fixed.

I also confirm the accuracy of the sensor location by paying $40 to an online Toyota Tech guy.
 
To clarify, when I started to get these codes, I tried the suggested comments on here with resetting using the obii scanner and replacing the gas cap since it was a cheap fix. Although it seemed to work, I couldn't tell as the code would pop up every 200-350 miles. Then, after a year or so, the error would pop up much quicker, every 75-100 miles or so. At that point, I just decided to change out the O2 sensors and see what happens. But unfortunately, luck was not on my side. So, I begrudgingly had to change 1 of the cc. Seemed to work for a little but after more research, it was expected that i would have to change the other cc soon as well. And, well, soon enough, I had to change the other cc!! haha. Emissions here is every 2 years so I took the long route of fixing this. haha. :reddance:

Anyways, as others have suggested, it could be a simple fix as resetting the codes or a gas cap but could be as pricey as replacing both cats. Good luck!

So you drove it for over a year with a faulty O2 sensor and then you were surprised to find out that it ruined your catalytic converter?

Resetting OBD2 codes blindly can be a recipe for a big repair bill. The whole reason for the system is to alert the owner and mechanic of a malfunction.

Don't just blindly reset the OBD2 computer just because you have the ability to. You should reset the codes AFTER you make a repair.
 
So you drove it for over a year with a faulty O2 sensor and then you were surprised to find out that it ruined your catalytic converter?

Resetting OBD2 codes blindly can be a recipe for a big repair bill. The whole reason for the system is to alert the owner and mechanic of a malfunction.

Don't just blindly reset the OBD2 computer just because you have the ability to. You should reset the codes AFTER you make a repair.

Thank you for the lecture Mr. Mechanic :hippie:
 

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