Originally Posted By: INDYMAC
Is it possible that the Shell nitrogen fuel additive would cause nitration abs to increase on a UOA for an MPI IC engine?
Yes. The active ingredient is polyetheramine, which contains a C-N bond. If PEA is present in the oil due to blow-by or fuel dilution it will read as nitration, increasing the value above what would be seen if fuel or additives containing PEA had not been used.
Ed