OpenFlash OTS - CEL P0137
 

Headers: JDL UEL Catless
Map: OTS Stage 2 UEL 2.06

Over the past 2-3 months, I've gotten CEL P0137 (Rear 02 Sensor LOW VOLTAGE) randomly at 3 different occasions. The first time it happened, I just cleared the code and ignored it. From my understanding it was a code related to the Rear 02 Sensor which should be disabled with the tune as I'm running catless headers. I'm really not sure why I am getting this code (I've not gotten any other code since I've flashed the OTS Map). After looking into the tune file in Rom Raider, it is set to ON and other codes related to the rear 02 sensor are OFF (P420). Currently, I have both sensors attached to headers and plugged in. Also, I don't have any exhaust leaks from what I can see.

Is this code something to be worried about? If so, how do I go about fixing this?

I'm wondering if anyone else has gotten this code?

I couldn't find much info in forums related to this code for users that are running OTS Maps so decided to post and ask. Hopefully this is the correct place to ask.

Thanks a bunch to anyone who decides to shed some light on this.

It's not unusual for some headers to trigger the P0137 code. I often has to do with the depth of the o2 sensor bung. In this case, there is no harm in just disabling the code in RomRaider so it doesn't pop up again.

Also, in disabling the P0420 code, the rear o2 sensor is not turned "off". They still work and provide a signal to the ECU. But the ECU doesn't run the catalytic efficiency diagnostic that monitors the amplitude of the voltage swings during closed loop conditions.

Thanks! I have a O2 spacer as well, I am guessing installing that will also avoid the code if it is related to depth of the bung?

Usually, the deeper the bung depth, the more likely you will trigger the low voltage code. No sense in installing it.

so I am using a bung for my borla uel, i just bought a used oft. I have to remove my bung before I tune to stage 2?

You don't have to. But I would recommend it. There is no reason to space out your o2 sensor.

Just to clarify, you're saying that its probably best to go in and turn that code off? I'm running a revworks header and I currently an waiting on an over pipe to resolve a slight leak (that's causing a 2096 fault) but I just cleared codes and found the 0137 present also.

Yes. If the issue is a rear O2 code and you're running a spacer then just disable the CEL code.

So after disabling the code, I'm noticing the engine is running smoother and my fuel trims are closer to zero than before. I haven't looked at logs yet but just by watching the oft while driving, they seem to be better. Could disabling this code be the reason or is it just a placebo ?

I'm so glad you made this thread. I thought I was going crazy. I got the same CEL twice already and couldn't wrap my head around it since the OFT should have prevented this code. Now I understand why. I had installed an O2 spacer that curves and it's pretty long which is why this code get's triggered at times. I'm going to remove it this weekend. The only reason I installed the O2 spacer is in the case that I have to make a trip to the dealer and flash the stock rom, I didn't want a CEL to be triggered because of the catless header.