2013 Serria 2500 6.0L P2097 P0430 P0420

[CRice2500 6.0]

I’m looking for advice testing and fixing stored and permanent codes. Truck is a 2013 Serria 2500 6.0L Vortec with 283737 miles. I have P0420 P0430 and P2097 codes using my live data I see both upstream and downstream sensor are fluctuating high and low is that defiantly saying the cats need to be changed ? Also P 2097 bank 1 high limit keeps coming back trying narrow down cause I will attach photos of freeze frame when code occurd some live data photos thank in advance 

[richard wysong]

The alcohol percentage is way off, Try resetting that and see what happens

[newdude]

Could be bad oxygen sensors.  Alcohol content on this year HD truck is a "virtual" flex fuel operation so it uses the oxygen sensors to calculate ethanol content.  It could also be bad fuel causing the high alcohol.

 

If you attempt at all to put in new O2 sensors, use GM only (AC Delco OE).