The lowering of carbon dioxide emission is world pursuit which is written in international agreement. It concerns all economy sections, especially motorization. In this last case the lowering is essential, since almost all fuel used for powering vehicles comes from nonrenewable resources. Using these fuels means a one-way carbon motion from underground lode to earth atmosphere. This process has to be immediately stopped. For several years there have been taken actions in this direction. There are both legislative and technical actions. However, the reports which were published in 2016 shows that despite the efforts and engagement of considerable means, the effects are mediocre. There has been noticed, that, though the lowering of carbon dioxide emission determined in bench tests has been attained, it is impossible to notice this progress in natural operation of vehicles. The causes of such a state are sought mainly in incompatibility of test conditions to the real operation of vehicles conditions. Assuming that the carbon dioxide emission is (quasi) directly proportional to fuel consumption, in the article there has been proposed the method of solving the problem of removing divergence between test and operational data. There has been suggested the different attitude to bench data analysis and implementation of new calculative procedures in a way to reach the correlation between the test and operating fuel consumption.