## 1 Introduction
In the first case, the driver, by moving the fuel supply control lever, sets the diesel speed mode at which the regulator reduces the fuel supply. Acceleration of the car at any position of the control lever occurs when the diesel engine operates according to the external characteristic, which significantly reduces the driver's ability, depending on the environment, to choose the optimal acceleration intensity in order to save fuel and reduce emissions of harmful substances. In diesel trucks with all-mode control during acceleration, it is advisable to set the fuel control lever to a position close to 80% full and change gears when the speed in the engaged gear stops increasing [29]. Other parameters controlled by the driver affect the amount of harmful emissions and fuel consumption much less compared to the position of the fuel control lever and the rotation speed at the moment of gear shifting [30]. Exhaust gases from cars in covered parking areas pose a danger to human health and life. Sources of exhaust gases are any vehicles with a running engine. The more cars there are, the higher the concentration of harmful substances released in the air. This effect is also noticeable on busy highways or during rush hour traffic jams. However, even one car with an open engine creates discomfort for people around and causes irreparable harm to human health. Having summarized the experience of the listed works, the authors came to the conclusion that the greatest harm to human health and nature is caused by vehicles in cramped conditions operating at low engine speeds [31]. Currently, ensuring appropriate indicators of emission standards in exhaust gases is carried out using active and passive methods. Of course, exhaust emissions depend primarily on the type of fuel feeding the engine [22; 32]. Passive methods play a crucial role in ensuring appropriate emission indicators. One such method involves the manufacturing of car mufflers (tailpipes) with various purposes and shapes using deep-drawing steel [33]. Another approach focuses on optimizing the noise reduction performance and efficiency of the muffler. This is achieved by employing an optimization design method based on acoustic transfer matrix and genetic algorithms [34]. Additionally, the design of an optimized muffler in accordance with standard specifications and FSAE rules is undertaken to achieve optimal muffler and engine performance [35]. Addressing the issue of low-frequency noise generated by internal combustion engines, several existing muffler design methods, such as the quarter-wavelength tube theory and the Helmholtz muffler, are examined and compared [36]. Passive exhaust gas reduction methods include the shaped solution, e.g., KZ Pat. 3194 [37] or RU Pat. No. 2 364 736 C2 [38], and primarily catalysts [39]. Precious metals, such as platinum, palladium, which contributes to the oxidation of CO and CH, and rhodium, which neutralizes NOx, are used as catalysts [40]. However, the presence of such valuable metals in the composition increases the cost considerably, even if their total weight is only 2-3 \(g\) of the total weight of the device's body. Moreover, catalytic converters have a limited life span, and their replacement is necessary every 100-150 thousand km. This is because the cells of the catalytic converter are made of ceramic, a fragile structure that has the property of being quickly destroyed depending on the exhaust gas flow, temperature difference, and type of fuel. When ceramic honeycombs are destroyed, they turn into small particles, which, when they get into the engine block, leave scratch marks on the walls and lead to considerable wear of the entire block [41]. In the pursuit of enhancing the efficiency and performance of automotive exhaust systems, the utilization of active ultrasonic technology has emerged as a promising avenue for innovation [42; 43]. The ultrasound method differs from most other methods in that it is designed to clean large gas particles and cannot completely rid them of more harmful, small particles.