I had me service light come on, ran code, P2A00, found that was the Bank 1 Sensor 1 O2 sensor. I bought a DENSO O2 sensor off the internet and replaced the sensor. I am now getting codes P1148 Closed Loop and P0031 HO2S Heater Control Bank 1 Sensor 1. I tried some basic forum searching but cannot find anything specifically related to these 2 codes AFTER already replacing the O2 sensor. I have cleaned and greased the connectors several times, I cannot see or feel any fraying of wires. Is it possible the new sensor is bad? I did try just plugging the old one in (not in exhaust man just electric) and still received the same codes. Is there a drive cycle or ECM reset procedure to "program" or "learn"? I am stuck at this point.

BTW - New User, great site, great info. Thanks!

Anyone?

Did you reset the ECU after changing the O2 sensor?

How many miles are on your car? It may still be under the powertrain warranty.

Welcome to NICO!

I would personally try switching the sensors from side to side. You'll know for sure if the sensor is bad that way... If you get the same code, then you know it's something else. Keep us up to date!

I did reset the ECU with the gas pedal pressing sequence and was successful but the SEL illuminated as I was backing down the driveway, off about 1-2 minutes.
I was thinking about swapping the o2 sensors or even testing them as well. I believe I saw a video to test with a multimeter and a torch (propane\butane).
I also wanted to ask if there was a way to get a voltage reading at the connection for the female side the sensor plugs into. Does anyone know what kind of readings I should have from there?
Thanks for the replies guys! Keep you posted.

Try consulting the FSM for troubleshooting.

http://www.nicoclub.com/archives/infini ... nuals.html

Go to the appropriate year/model and open the EC.pdf

I am having some on going issues with these damn codes. I have replaced both upstream sensors with brand new Denso's. I am still getting p1148 p1168 p0031 and p0051. What is the problem? I guess I need to test voltage on connectors to the sensor to see if I am getting voltage. Anyone have numbers or any ideas for that matter? I am confused.

I am trying to follow the steps outlined in the following attached PDF on page 159.

http://www.nicoclub.com/FSM/G37/Sedan/2009/EC.pdf

But I am at a stand still since I have already replaced the sensors it leads me to believe this may be a connector or harness issue and I am not completely clear on how to test them. Any ideas?

Have you checked for leaks or faulty cats? The sensors expect a closed system and if it has a bad weld, crack, whatever, then it can show issues. Otherwise, at this point, I'd consider the dealership to troubleshoot.

I might be reviving an old thread but I was never able to fix the original problem. Check engine light is still on and now its time for tag renewal, unfortunately impossible to do with a CEL. Pull codes and came up with this awesome list:
P1148 Bank 1
P1168 Bank 2
P0037 Bank 1 Sen 2
P0057 Bank 2 Sen 2
P0031 Bank 1 Sen 1
P0051 Bank 2 Sen 1
P0150 o2 circuit Bank 2 Sen 1

What is all of this pointing at, even a guess is appreciated. My scanner can't pull Live Data which may help. Only thing I can think of is wiring harness or faulty cats, any opinions?

Anyone have any ideas? Don't really feel like tossing $600 and labor to replace cats as a guess.

We can only point to the FSM and troubleshooting each error code. What is the commonality between them all (if any)? If you've replaced some parts you can at least remove them from the list of possible culprits.

kickin_it wrote:I might be reviving an old thread but I was never able to fix the original problem. Check engine light is still on and now its time for tag renewal, unfortunately impossible to do with a CEL. Pull codes and came up with this awesome list:
P1148 Bank 1
P1168 Bank 2
P0037 Bank 1 Sen 2
P0057 Bank 2 Sen 2
P0031 Bank 1 Sen 1
P0051 Bank 2 Sen 1
P0150 o2 circuit Bank 2 Sen 1

What is all of this pointing at, even a guess is appreciated. My scanner can't pull Live Data which may help. Only thing I can think of is wiring harness or faulty cats, any opinions?

Kickin_it - yes, I know exactly what that is. It's a bad 02 sensor fuse (15 amp I think). I had the same issue and only figured it out after my battery needed to be replaced. There is a fuse box behind the battery, at least on an Infiniti M35. If you take out the battery you can access it it. Let me know if that solves it.

1stInfiniti wrote: ↑

Mon Nov 28, 2016 6:37 am

kickin_it wrote:I might be reviving an old thread but I was never able to fix the original problem. Check engine light is still on and now its time for tag renewal, unfortunately impossible to do with a CEL. Pull codes and came up with this awesome list:
P1148 Bank 1
P1168 Bank 2
P0037 Bank 1 Sen 2
P0057 Bank 2 Sen 2
P0031 Bank 1 Sen 1
P0051 Bank 2 Sen 1
P0150 o2 circuit Bank 2 Sen 1

What is all of this pointing at, even a guess is appreciated. My scanner can't pull Live Data which may help. Only thing I can think of is wiring harness or faulty cats, any opinions?

Kickin_it - yes, I know exactly what that is. It's a bad 02 sensor fuse (15 amp I think). I had the same issue and only figured it out after my battery needed to be replaced. There is a fuse box behind the battery, at least on an Infiniti M35. If you take out the battery you can access it it. Let me know if that solves it.

Thank you so much! I had exact same issue and even though I've ended up changing all upstream sensors, at least I did them myself, so it's not as painful to feel uninformed and thus lose money and time.