2005 Honda Accord, 2009 Honda Accord, 2010 Ford F-150. ALL had the same codes, an O2 sensor in the exhaust chain leading some to believe the catalytic convertor is going bad.
If you google 02 sensors and ethanol, you’d be likely to run across a term “wide-band” 02 Sensor and ethanol’s effects on it....
You won’t find much else because the ethanol industry doesn’t like publicity about ethanol destroying seals, gaskets, O rings, fuel lines, and sensor, etc.....
I finally quit using QTrip because a mech engineer friend told me they’ve been caught using much more ethanol in their gas than they report (up to 10% is their limit).....
I found that using brands of gas that aren’t discount like Q and Racetrak, my sensor trips are not near as frequent....
Three cars/trucks - same problems in 5 years....that’s not chance...
Hmmmm.....my Civic is a 2009. What symptoms did you have?? I wonder if this is a sensor supplier problem/bad batch. It can't be a generic ethanol problem, because too many other cars have/do run just fine with "gasohol".
My Civic has one "glitch".....when cold, it tends to "stutter" somewhat during somewhat rapid acceleration (not "floorboarding"....just "running up through the gears"...rpm might hit 5000 (8000 redline)). As long as I keep it to 3000 rpm max until it fully warms up, it is just fine. I have attributed it to the fact that the Civic is an SI and requires premium gas (and yes, I bought it for my second "teen-age hood"). Six-speed tranny and all the "bells and whistles". I still haven't figured out all the stuff the sound system can do. It's better than the one in my house!