One of the main pollutants in automobile engine exhausts is NO. Hydrocarbon-based selective catalytic reduction (HC-SCR) is one of the most preferred methods to reduce NO at the expense of unburned hydrocarbons, which are also present in automobile exhausts. In this study, we have developed a detailed kinetic model and analyzed the selectivity of NO reduction to various products (N2, N2O, and NO2). The optimal operating conditions for the maximum reduction of NO to N2 are also explored. Various phenomena including coking and the oxygen-rich nature of the catalyst surface are found to occur as the amount of oxygen in the inlet is varied. The influence of O2 and temperatures on the selectivity of NO reduction is discussed in detail. © 2017 American Chemical Society.