"Right 02 Fail" DTC in Open Loop Mode?

I've been running 2bar setup for awhile now, in SD mode, in open loop mode.

The other day I was in heavy traffic and the SES light came on for first time in a long time.. it came up in Datamaster as "Right 02 Fail".. I checked LT1_Edit and dont see anything for 02 ignore.. so Im a little confused.

Anybody else ever get something like this? Or should I be checking my harness? I thought in Open Loop the sensor checks were ignored.

I've been waiting for someone to respond.. Could it be even though the O2's readings are not used in SD to correct the mixture the PCM is still doing high/low/switching diagnostic checks against the voltage readings. Just in case you may decide to turn them back on some day, they will be operational ?? Just a guess till someone chimes in.. With your 2Bar tune what do the O2 voltages look like ?

Yea I was looking thru the Tunercat software and found an option to disable the "02 Fail" code from showing (I think), even thought I dont know why it gets set in SD mode.

My o2 values float around depending on the mixture, no switching, If Im cruising then it's mainly flat wherever the mixure is... accellerating makes them move more but not switch like they do in closed loop

What was the exact code you got? Most of the O2 codes only set in closed loop, but the heater circuit codes will set on cold start.

The actual code was "MALF 63 Right 02 Fail" - I remember the SES light popped on when I was in rush hour traffic, after a about 20mins of city driving.

I thought it was strange. Do you think any combination of that 02 sensor signal wires being loose/shorting might cause it? I did cut the harness at one point to wire in the WB02 but disconnected that and wired back to stock and disabled closed loop (awhile ago).

I just dont want the SES light on or the fans to come on, I disabled the function in Tunercats so hopefully it doesnt come back.

Dookie, where did you cut the harness, hopefully not the O2 pigtail side of the connection.

Dookie, where did you cut the harness, hopefully not the O2 pigtail side of the connection.

I cut it by the PCM to avoid crawling under the car.. way easier.