heat exchange of pulsating exhaust gas flows in the exhaust system of piston internal combustion engines (ICE). Experimental studies were carried out on a single-cylinder full-scale model of an automobile ICE of dimension 8.2/7.1. Gas-dynamic, consumable and heat exchange characteristics of pulsating flows in the exhaust system of different configurations (equipped with and without an ejector) are given in the article. It is shown that the installation of an ejector in the exhaust system leads to stabilization of the flow and allows to improve the cleaning of the cylinder from the exhaust gases, as well as to optimize the thermal state of the exhaust pipelines. The experimental data were supplemented by numerical modeling of the working process of a full-size diesel engine (dimension 21/21) produced by the Ural Diesel Engine Plant. Simulations were also performed for engines with different exhaust system configurations. It has been established that the use of the ejection effect in the exhaust system of a diesel engine leads to an improvement in cylinder cleaning up to 10 % and a decrease in specific fuel consumption by an average of 1 %.