Good morning folks,

I was wondering about the ECM data being sent to my car's systems if my catalytic converter is good but my downstream o2 sensor is reading out of range triggering a CEL. Will the ECM dumb down the timing, fuel mixture, EGR function etc.? I can clear the CEL by disconnecting the battery and it will stay off for a day or so, but I can't really tell the difference in the way it drives with or without the CEL on. Can anyone say definitively if a 2003 Honda Civic will act different with a downstream o2 sensor reading out of range as opposed to not? Thanks!