P0138 cel problem

Looking for some advice on cel code p0138 bank 1 sensor 2 high voltage. I replaced sensor but light came back on. My afr gauge is reading rich about 13.1 or so when not in boost. I thought it was exhaust manifold gasket leak so I replaced it on passenger side of motor, but light still on. Would the leak have to be on the side where the problem is? Any advice on what to look at would be great. I will check the electrical connections also make sure that is mot the problem. Thanks 2007 4.0 v6 tacoma supercharged automatic.

 

Looks like you'll need to actually replace the A/F sensor Bank 1. It's not functioning properly and causing the rear sensor (which was probably never bad) to read wrong. Not sure why the ECU doesn't pick up a bad A/F sensor, but appears to be pretty common (according to about 5 minutes of googling)

Also this is the wrong section to post this question.

 

Ok thanks. Sorry first time starting a thread. The bank 1 sensor 1 is new already. So both sensors on left side (driver side) are new.

 

Just wanted to post how I fixed my truck. The check engine light came on for p0138, so I replaced the sensor. Next day light was back on. My wideband afr sensor was reading 13 the whole time, so I pulled it out and checked to make sure it was working properly. Once I new the sensor was working I figured let me swap air fuel sensor from bank 2 to bank 1 and see what happens. My wideband afr went back to reading 14.7 or so at idle. Being I just spent almost $300 On sensor I was hesitant to keep changing them out if they were still good. So I installed the new one and everything is fixed now. No more check engine light. So if you have p0138 code and a new sensor didn't fix the problem, check the air fuel ratio sensor. Mine didn't throw a code for that sensor, but that's what was causing my bank1 sensor2 to throw a code. Hope this helps anyone with 2 generation Tacoma 4.0 v6.

 

Do you know if this is drivers side for a 2009 as well?