O2 Sensors Question

I was trying to sell my 2005 Tundra and the last person to test drove it kept turning the truck on and off and eventually triggered a check engine light. Grrr. So I plugged in my OBDII reader and it said P2238 "O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 1". So... I'm guessing that by doing the off and on it helped a teetering O2 sensor meet it's fate?

Is this something I need to replace all 4 sensors, as they are all going bad? Or....? Any direction would be greatly appreciated. Thank you!

 

Replace the failed one and sell it.

 

Before jumping to replace anything, try resetting the code and drive it around. This could just be a fluke, with this specific code at least.

If the code returns in 25-30 miles, it's fingering the driver side sensor between the exhaust manifold and cat (upstream). I usually recommend replacing O2 sensors in pairs, i.e. if you're doing the one pre-cat, to the one post-cat on the same side. Buy Denso parts on this one.

 

Thank you for your insight. The check engine light did go away. I will see if it returns, if so I will replace the O2 sensors in pairs.

 

Idiot test drivers. I sold my 4Runner before moving to Japan and the dude who test drove it decided to put it in 4WD and do circles/doughnuts on hard pavement. When he returned he said “hey dude - something wrong with your 4 wheel drive” left quickly. Had to fix one of my hubs. F’ing a$$hats.

 

I don't know if the sensors are in the exact same location as my 2001, but the upper/driver (bank 1 sensor 1) isn't too bad to do and can be done from underneath. However, the upper/passenger was a total bitch, you need to reach behind the engine from above to disconnect the harness.

Lower sensors aren't too bad, can be a pain if the nuts are old and rusted...but at least they are easily accessed.