ECU randomly disables closed loop

[DerBuegler0815]

i'm havin a problem where my s300 v3 doesn't stay in closed loop. I can't really see what triggers it or if I have something set up wrong.

In the included Datalog it happens right around 8 minutes. I step off the gas for a few seconds and out of nothing it doesn't regulate my afr anymore..

I'm using a AEM Xseries UEGO wideband and a P28 ecu.

[Hondata]

It is the wideband input. It goes to 4.5V.

[DerBuegler0815]

OKay, it acts up as soon as I let of the throttle and my gauge just reads off scale lean. Right after that I continue driving and it stays in open loop as long as I turn the ignition off and on again ( sry, I forgot to include that detail). is it because i set the lambda conversion table only up to 4.51v and the program bugs out? I'm gonna change that and see what happens

[DerBuegler0815]

That did the trick. Thanks for the fast response :)

[Hondata]

To me it seems like it is the wideband controller. The AF is following the voltage input, so when it shows full lean and open loop is the because the input voltage is 4.5V.

[DerBuegler0815]

I don't quite understand what you are explaining but setting up a 5v point on the lambda-voltage table seems to have helped.

No its throwing a cel after 20 minutes of driving... error window states "primary o2 sensor"

I guess that is because i left d14 unused and the plug is flappin in the breeze.

[DerBuegler0815]

seems like 13 minutes. not 20. right around 13:48 MIL was triggered stating "primary oxygen sensor"

[DerBuegler0815]

Aahhh sorry. Dont mind me spamming posts.

I get what you mean. The afr goes off scale when i let off the throttle and if i do it for to long the ecu thinks my o2 sensor is broken...
Is there a way to get around that?
Im gonna do research about my afr controller

[Hondata]

Unless I'm missing something when the AF goes full lean the input voltage is 4.5V. So the wideband controller is the problem, not the ECU.

If there's some other place in the datalog where you see something different let me know.

[DerBuegler0815]

The wideband controller's highest output is 4.50v so it is supposed to be like that. I was a bit confused what you meant.

Ive changed a few fuel trim settings and now it seems tp work. I just drove around for an hour no problems. I have found these recommendations in another thread. I only changed the top left one to be a bit faster. And i optimized my fuel table a bit more. My ltft is a steady 0.

Seems to work now. The main cause seems to stay a mystery