CEL Help ECU

[ccool91]

I recently had my transmission blow up.. 2006 4x4 132000 Miles...
Had it replaced with a Factory new tranny, since I got the car back their has been a code and cel for bank two downstream o2 sensor. Last night I replaced it and when my wife went to work the cel came back on for p0158; the same o2 sensor again, and this time p0606 for a bad ECU. I have cleared it and it comes right back. Dunno if there was an install mishap during tranny repair or if this thing is a lemon.
Any idea what's going on?
Any information is greatly appreciated!
Thank you for your time,

 

[BlackWorksInc]

Clear the DTCs and install a new Bank 2 Sensor 1 if all the wiring for the oxygen sensors looks good. That DTC can be a bit tricky as it indicates a Bank 2 Sensor 2 circuit issue, but there's a strong possibility that it's caused by a failing AFR sensor and not the Sensor 2 Oxygen Sensor.

As for the P0606, it's possible that's being cause by the failed/failing O2 sensor. I do recommend trying a Bank 2 Sensor 1 first if the wiring looks good.

 

[ccool91]

Thank you for the input! I will check wires tomorrow and if they look good order the bank 2 sensor 1.
Thanks again!

 

[blackoutt]

this is timely for me. I was just playing with trying to trick the rear O2 sensors with resistors and capacitors after removing my front catalysts during a header install and caused a p0606 that would not clear. All my research indicated that it was not and ECU issue and was truly O2 related only so I reversed my additions to the wiring and the 606 cleared. Blackworks is right though if the primary AF sensor is off it can cause the downstream O2 to read incorrectly too. Odd that it wouldn't log an upstream sensor fault but I work in engine diagnostics so I understand how that can happen lol.

 

[BlackWorksInc]

this is timely for me. I was just playing with trying to trick the rear O2 sensors with resistors and capacitors after removing my front catalysts during a header install and caused a p0606 that would not clear. All my research indicated that it was not and ECU issue and was truly O2 related only so I reversed my additions to the wiring and the 606 cleared. Blackworks is right though if the primary AF sensor is off it can cause the downstream O2 to read incorrectly too. Odd that it wouldn't log an upstream sensor fault but I work in engine diagnostics so I understand how that can happen lol.

What's worse is that the faults must be ridiculously small, because while the sampling rate isn't great on the Techstream (to be fair I haven't had the opportunity to throw the Pico-Scope to verify, I am flat rate after all lol); I have never been able to find definitive answers on what the ECM is misinterpreting on those damn sensors. I've had a Tundra that literally everything on the front AFR reads correctly, but it keeps setting a PO158 until it's replaced (even though the new sensor registers exactly the same as the old one). The only thing I can think of is that the ECM is "lying" to me and not giving me accurate data when requested and the fault is kept between the AFR and the ECM and is not being translated to the end-user (technician with the scantool). It's a frustrating situation because the only real solution is to just throw parts at it and hope it fixes it (which it does usually), which is annoying from a diagnostic stand point.

Post Note-

Spoofing the rear O2 sensors requires some trickier as the P0606 is thrown because of quirky ECM grounding through the AFR/O2 Sensor circuits if I remember right (I believe that's what the TSB mentioned.) I'm not entirely sure if they are doing something weird like pulsing the ground circuit to check for status (this is something that's apparently done on circuits like the shielded ground in the reverse camera circuit on our newer models, go figure since it's not mentioned anywhere in the damn FSM -.-0 )