The vehicular emission of non-methane organic gases and compounds (NMOG) plays an important role in the formation of ozone and its contribution to the "photochemical smog" and therefore has been one of the main focuses of automotive development, in order to minimize its environmental impact.Some countries in Europe and the USA already control the NMOG emission, mainly composed of non-methane hydrocarbons (NMHC), aldehydes, ketones, and non-burned ethanol (EtOH). In Brazil, where the high scale flex fuel market is in series production since 2003, currently 0.05 g/km of NMHC are allowed for passenger cars (based on the ongoing PROCONVE legislation, L6 stage). The deduction of the non-burned ethanol fraction is also allowed [1] [2] [10].In order to support the NMHC reduction and minimize the impact of flex fuel engines on the environment, this study presents some engine calibration options at different PFI vehicles, considering the usage of the heated cold start system based on heated fuel rail.