Vehicles are equipped with more and more devices to improve the comfort of traveling. They are usually powered by electricity generated by the engine, which translates into an increase in its loads and, as a consequence, fuel consumption and emission. However, there is no information about the possible increase in the amount of other harmful components contained in the exhaust gases. Often this result is inadequate to that obtained during the operation of the vehicle, where the obtained fuel consumption is higher. As part of this article, tests were carried out in real hybrid vehicle traffic conditions on the same test route using an analyzer from the PEMS (Portable Emission Measurement System) ¬ SEMTECH DS Sensors Inc. The analysis of gaseous components of exhaust gases together with the exhaust mass flow probe and the GPS system made it possible to calculate the pollutant emission.. On this basis, the actual mileage fuel consumption of the tested vehicle was calculated using the road emission of carbon-containing compounds (carbon balance method).