My question is about the OEM O2 sensor.

In order to get my car to pass emissions I disabled the O2 feedback with the commander. I then leaned out the idle & cruise fuel cells that are hi-lighted on map tracer (I also leaned out the adjacent cells due to averaging)

Car runs good & I passed emissions.

Without resetting the fuel cells & reengaged the O2 sensor feedback. The car runs really rich @ idle & I can feel surges during cruise with corresponding rich/lean indications.

I figured it needed to "learn" the new setting & tried to dive it that way for a week. No change, runs like **** (rich & surges), idle hunts & stalls. All around pain in the ***! As soon as I disabled the O2 feedback everything settles down & driveability is normal again.

Is there a limit to the amount of O2 feedback correction the PFC will accept? In other words should I have the closed loop map tuned closer to stoich?

I bought a new OEM O2 sensor & the car acted exactly the same, so IM confident it's not a bad O2 sensor

FYI, I originally had my car tuned on the dyno with a wideband O2 sensor.

 

Any feed back system is designed to operate within a set of parameters.


Since you changed an area of fuel cells and then turned O2 back on, you have upset the set of parameters thus throwing it out of it's control range.