[Dave92N54]

Originally Posted by Aria335iN54

Can you share your idle log

+1.

I just took a screen recording of my idle I can post if necessary. It was idling fine, no clue why I decided to screen record and not log. Ill see if I can get a log of it idling normally and when it does the oscillation tomorrow.

[TiAgAu]

Originally Posted by gster109

I think that has something to do with msd80 vs 81 because 81 monitors 02's much more accurately. I think the lack of removing that 02 check as part of the mhd catless tune has to do more with it at the end of the day.

This was my thoughts aswell with dme's. It was talked about earlier in this thread msd81 also does the same so its not the issue.

[Aria335iN54]

Originally Posted by Aria335iN54

Just wondering is this tune tweak involves deactivating rear O2 sensors?
Cause I have heard a lot against it as they also function to trim primary O2 readings

Car Abuser, if you could shed some light on rear O2s status would be great.

For those who have this issue and say idle is fine, if you listen carefully to the idle you will notice the idle tone changes sometimes. Not a misfire or rough idle but once you disconnect rear O2s and afrs stabilise around 14.7 then you see how smoother the idle becomes.

Also I noticed excessive soot on my O2 sensors and exhaust pipes which likely linked to this issue.
If anyone noticed the same please confirm.

[CarAbuser]

Originally Posted by Aria335iN54

Car Abuser, if you could shed some light on rear O2s status would be great.

For those who have this issue and say idle is fine, if you listen carefully to the idle you will notice the idle tone changes sometimes. Not a misfire or rough idle but once you disconnect rear O2s and afrs stabilise around 14.7 then you see how smoother the idle becomes.

Also I noticed excessive soot on my O2 sensors and exhaust pipes which likely linked to this issue.
If anyone noticed the same please confirm.

No change to O2 sensor functionality, currently I have just set the fuel bias during catalyst test to 0 so that the routine is still running but it doesn't mess with my AFR.

My OCD isn't happy with that but BMW purposely made it difficult to disable the catalyst diagnostic routine so a logic change might be required. It might be easier to alter the test criteria so that the diagnostic routine passes and the loop stops.

[Aria335iN54]

Originally Posted by CarAbuser

No change to O2 sensor functionality, currently I have just set the fuel bias during catalyst test to 0 so that the routine is still running but it doesn't mess with my AFR.

My OCD isn't happy with that but BMW purposely made it difficult to disable the catalyst diagnostic routine so a logic change might be required. It might be easier to alter the test criteria so that the diagnostic routine passes and the loop stops.

Thanks a lot.
Now gotta find a tuner which can understand these and be bothered to apply in their tune!
Usually more power is their main agenda to attract customers...

[DefaultGate]

Originally Posted by CarAbuser

No change to O2 sensor functionality, currently I have just set the fuel bias during catalyst test to 0 so that the routine is still running but it doesn't mess with my AFR.

My OCD isn't happy with that but BMW purposely made it difficult to disable the catalyst diagnostic routine so a logic change might be required. It might be easier to alter the test criteria so that the diagnostic routine passes and the loop stops.

Birring this thread back because I have been trying to sort this issue for years now. My AFR's ping to 17, and also 12 randomly, and I have always thought it was due to CAT readiness testing.

CarAbuser, what was the name of the parameter you changed? Is it in the public XDF? I would literally pay for you to show me lol

[CarAbuser]

Originally Posted by DefaultGate

Birring this thread back because I have been trying to sort this issue for years now. My AFR's ping to 17, and also 12 randomly, and I have always thought it was due to CAT readiness testing.

CarAbuser, what was the name of the parameter you changed? Is it in the public XDF? I would literally pay for you to show me lol

Not in public XDF but there's a discussion on it over on the spool street forums.
You'll have to google your way there, the thread title is "Readiness - Catalyst".

[trb1]

Originally Posted by CarAbuser

Not in public XDF but there's a discussion on it over on the spool street forums.
You'll have to google your way there, the thread title is "Readiness - Catalyst".

looks like theres only public information on how to fix this in I8A0S files. Nothing for IJE0S

[CarAbuser]

Originally Posted by trb1

looks like theres only public information on how to fix this in I8A0S files. Nothing for IJE0S

Post in that thread and request them. It's not hard to find the tables but nobody will bother unless you ask.