Mexican Diesel Fuel - Sulfur Levels Update

OF COURSE a DPF is not designed to burn off sulfur. Numerous times I have written that the process of burning off the soot deposits in the DPF, known as regeneration, also has the side benefit of burning out deposits of sulfur compounds in the SCR. It is those sulfur deposits in the SCR which cause NOX emissions to go out of spec, which in turn leads to the Check Engine Light on, as well as a warning of "Poor Quality DEF", and the presence of codes P2BAD and P20EE. Vehicles that do not use DEF never have any issues with sulfur in the fuel, and not all vehicle makes and model years that do use DEF have issues.