Hondata

It should not be connected directly to the battery. You should connect it to one of the extra spots on the under dash fusebox that is switched. You should also try moving the ground to the thermostat housing.

that s how i got it wired up first, i tried the battery to see if it makes a difference, it doesn t.
the link is switched with a relay, not always on of course
also tried different ground spots to be sure, thermostat housing was the first option

Post your calibration and a data lot showing the issue

ok, i ll get that tomorrow morning
your help is much appreciated
thank you

here is the calibration and a log recorded from home to work
I didn t get any cel this time
I ll keep my laptop connected until I get it

got it

Try running closed loop with a voltage target instead of a lambda target and see if that has any effect.

no :(
same cel, got it today

seems to happen less often when it s colder outside