Wide-boiling liq. products of pyrolysis of plastics wastes from 3 com. prodn. plants were analyzed for chem. compp. by gas chromatog. coupled with mass spectroscopy and for tech. properties and then sepd. by distn. into 3 low, middle or high-boiling fractions (b. up to 170 degrees C, 170-210 degrees C, and 210-280 degrees C, resp,) The narrow-boiling fractions were added to com. gasoline and Diesel oil (up to 40% by mass). The resulted blends were studied for d. fractional compn., kinematic viscosity, stability (after 30 days of ageing as well as flash freezing and cold filter-clogging temps. to check their accordance with the respective standards. The stability of some blends contg. the middle or high-boiling fractions was not satisfactory (increase in viscosity, formation of ppt. The gasoline blends contg. up to 20% of the low-boiling fraction or up to 5% of the middle-boiling fraction as well as Diesel oils contg. up to 20% of the middle-boiling fraction or up to 25% of the high-boiling fraction met the standard requirements for the resp. motor fuels.