There is alot of inconsistency with E85 as well, the 85%ethanol is supposed to be the minimum, but we get vehicles in the dealership with anywhere from 60% to 90+% ethanol content in the fuel, and these are customers who consistently use E85 and don’t mix regular fuel with E85. Not having 02 sensors, etc.. to compensate for the changes in the content would be frustrating to tune(if not damaging) on a carbuerated engine.