ok gents, i need some help/clarification. i've been reading all morning about disabling the rear O2 sensor but the problem is the posts go back a few years, might be evo ix only, or might be outdated.

i installed a cobb high flow cat. the SES light came on today. said code ---- EDIT: the code was wrong, apparently evoscan dtc scanner isnt correct... at all. removed this code to prevent future confusion.

that's fine, i can disable my rear O2 sensor in ecuflash, but the part i'm getting confused about is the rear O2 heater.

if you just disable the rear O2 and change nothing else, will this cause a heater code being thrown or will this break the O2 sensor?

i read about a software rear O2 simulator patch but i think it was part of tephra mod for evo ix.

i also read about a hardware fix with a resistor but think that was evo ix too.


note: the car in question is a 2012 gsr. i have openport 2.0 + ecuflash + evoscan. also i'm purchasing an aem uego to install in the rear o2 location anyways.

 

Why not just disable it and pull the sensor out all together? You would then have a spare if ever needed.

 

yea i will as soon as the wideband comes in.

the thing i need to know is can i just disable rear O2 with out issues with the rear O2 heater?

 

i found this on evoXforums that i think answers my question:

if i just disable the sensor in the ecu i will damage the sensor. i will wait till i get the wideband first.

mo

 

Yes, if the heater circuit is disabled the sensor will be ruined. Just so you know the heater is in the sensor itself. You can still pull the sensor out and just run 02 sensor bung plug.

 

yea, that's what i wound up doing afterall. pulled the sensor off unplugged it from the car completely. plugged it with an m18 x 1.5 bolt (which btw is sold at lowes as an oil drain plug.

flashed the ecu with bit 2 disabled.

 

well, the CEL light popped back up today driving to work even with rear o2 disabled. scanned it with the torque pro android app and the code is p0140.

i flashed ECU again, this time with DTC P0139 Disable 0x1 -> 0x0. i hope that takes care of it because my definitions dont have a method for disabling P0140.

 

you should quit cheap assing a 30k dollar and just buy a Cobb AP before you really mess something up

 

i wouldnt say i'm cheap assing it. i've considered the AP but felt openport was a better choice for flexibility and allowing me to learning my ECU. AP is better for ease of use.

either way i swung by cobb in plano, AP wasnt ready for 2012 at that point so unless they've rolled out definitions and maps for the 2012, i dont think i would be able to bypass the DTC codes with it.

it's really not that big of a deal. i removed my rear o2 sensor, as a result i get o2 sensor codes and now i get to figure them out.

 

anything new?
im in the same boat. test pipe, removed sensor=CEL.
I haven't tried disabling it in ecuflash yet.
please let me know of anything new with our 58010005

 

I couldnt stop the light from comming back with cobb ap myself so goodluck. I tried both options (option 1 on/off and option 2 on/off) and after driving for 20 miles it would always comeback anyways, so I got a DP with 2 bungs and a highflow cat for a stock 02. Hope it fixes my issue now(waiting on uicp so I can install them). Ive asked on cobb forums a bunch of times what else I could do but nothing that was suggested worked. So I keep getting the p0140 code.

PS I have a 2010

 

should fix it with a cat

 

Currently mine is fixed. No rear o2 sensor, no CEL.
I have some theories about the sequence of actions and their DTC reactions. I need to put about another 30-50 miles to make sure it's really gone.

 

Yes but before you change anything will you find the code you are throwing please?