Travelling in the urban environment is a complex activity as it is influenced by a multitude of factors, such as: infrastructure structure, traffic intensity, vehicle characteristics, weather conditions, driving style, etc. Completing an urban cycle at peak hours requires a transitory dynamic regime in a percentage greater than 80–85%, the rest of it, meaning stationary traffic jams, waiting times at traffic lights, pedestrian crossings, respectively road junctions (conflict points) and so many others.This percentage is significantly lower in the case of extra-urban cycle traffic. In this paper, an analysis of emissions, such as: carbon monoxide (CO), nitrogen oxides (NOx), carbon dioxide emissions (CO2) and parameters, as well as, oxygen (O2) and the measured or calculated lambda value (λ) is carried out from the internal combustion engines (SIE and CIE/ Euro 6) produced by vehicles moving in urban traffic. In this case, the emissions with the highest values are highlighted depending on the travel speed, load, time and thermal regime of the engines. The tests were carried out both on real traffic conditions (recording the data obtained necessary for the analysis) and in the specially equipped laboratory, on a dynamometric stand where the recorded cycles were implemented and the reproduction (modeling) of the maps of real traffic was carried out depending on time, speed of movement, the slope of the road and the gears as well. The vehicles under study were subjected to bench tests using the implemented cycle. These simulations could be carried out using the “Driving Cycle” option of the dynamometric stand software. At the end of this work, a clear highlighting (depending on the analyzed parameters) of the emissions of different vehicles is obtained and the main causes that directly contribute to them are highlighted.