25th327RS

iTrader: (2)

Need a little input or advice on this trouble code on my ls swapped Camaro.

P0155- O2 heater circuit malfunction, bank 2 sensor 1.

One would think bad O2 sensor, or bad ground, or bad power source to 02 sensor. I am troubled, as my tuner said he tuned it in "open loop". He said my 02 sensors were wired wrong, or plugged in backwards, something to do with them splitting opposite ways once it switched to closed loop....? Wasn't sure what he was talking about, and told me he tuned it in open loop and, I was under the impression that NO O2 sensors were functioning now.

Had no service engine light when I left, but now I get this code every three or 4 drives with it after clearing the code.

Did my tuner forget to shut something off if I am tuned to run open loop, or do I need switch my o2 sensors plugs so they are plugged in to the correct bank and have their functions turned on again?

five7kid

iTrader: (14)

Sounds pretty weird. What was the source of the harness, and what was done to it?

86White_T/A305

I fought this code and it ended up being an exhaust leak pinhole just around the o2 bung.I tried it all before that.. bosh o2's,ac delco,corvette rear o2s for fronts,then had best results using universal 4 wire denso's.No more code..and i hate having a code come up for any reason.Other than a shift light.. i dont need another indicator starring at me lol

25th327RS

iTrader: (2)

Harness is a 99 ls1 t56 Fbody harness integrated with a factory thirdgen harness per pockets walk-throughs.

I checked all wires and pin locations twice before installing it, and I do have ground and 12v at o2s still. I wasn't sure what the tuner was talking about with the o2s splitting when going to closed loop. Said most often, its just bank 1 plug is on bank 2 sensor and vise-versa.

Granted, if the car is tuned open loop, I should t get ANY O2 related codes....correct?

five7kid

iTrader: (14)

Probably means he tuned it ignoring the O2's, not that he turned off the trouble code.

25th327RS

iTrader: (2)

I called the tuner this morning, he wasn't available and got his voicemail, I know he has two cars to tune today, hopefully he has time toget back to me, and see what his thoughts are.

five7kid

iTrader: (14)

Did you completely depin the PCM connectors? Not hard to switch up something like this.

25th327RS

iTrader: (2)

The harness was completely dis-assembled and PCM connectors totally de-pinned. I will check again for o2 sensor pin locations when I get home, should only take a few minutes. I ohm'd out each wire twice after it was completed (checking pin locations as I went), so I am confident its pinned right......... Wouldn't be the first time I was sure and ended up being wrong though.

25th327RS

iTrader: (2)

High and lows to PCM ohm'd out good and pin locations were correct for both sensors. Ground and 12V supply was also good for both sensors. I also had the bank one sensor on bank one connector, as well as bank 2 on bank 2, not switched like the tuner had guessed. All wiring checks out, but I did find the bank2 O2 sensor was damaged. The end was close to the floor and looks like it contacted the floor with engine movement. The sensor I replaced it with was about 1/2 inch shorter, and gave me quite a bit more clearance here. Hopefully it was just this damaged sensor...... Still think that if the car was tuned to run open loop, that O2 sensors would have been set in a way to NOT set off the MIL. Maybe its not do-able? I am ignorant to tuning, I just don't know. Will keep this updated as far as my mil light coming back or not.

25th327RS

iTrader: (2)

Two of the wires were bared/ twisted as well as the end of the sensor being smashed

86White_T/A305

The tuner can tune the car in open loop and force it to stay that way during tuning but doesnt mean the o2's were set to not feedback the mil after tuning is done. You can set them to just not set off the mil even if it has a dtc ..or not set mil and delete/ignore the dtc period.When I first had codes for o2's my tuner just set them to not set the mil but the dtc would stay in the history while I tracked down the problem.Then i went back and he set it to report mil again after i solved my problems.I personally dont like setting a sensor to not report the mil on for any reason.

Hopefully you had just that bad o2 and all is well.If you can..get some heat reflective tape and wireloom to cover the o2 to prevent mishaps like it chaffing or wires getting very brittle from high heat.

25th327RS

iTrader: (2)

I drove the car to work today, and had to make a few stops on the way. So far, no MIL.

I just thought if the PCM was configured in a way to ignore O2s, that the O2s would be set in a way to not set a DTC, since its not being used. Apparently this is not the case. Like I said, I am ignorant on the subject of PCM tuning, haha.