A major issue with spark-ignition engines is their fuel inefficiency and negative environmental effects, especially in urban driving situations. This topic is of utmost importance considering the increasing apprehension over environmental contamination and the need for enhanced energy efficiency. The research’s originality resides in its strategy to tackling this issue without necessitating intricate engine changes, a manner not commonly used. The research uses a dual strategy that integrates both theoretical and experimental approaches. The theoretical component entails developing models to forecast the effects of different cylinder deactivation strategies on fuel consumption and emissions. Important factors to address in this theoretical model are the introduction of air into cylinders that are not in use and the stopping of fuel supply. The experimental component involves conducting bench experiments on a modified spark-ignition engine to verify the theoretical conclusions. These tests assess performance metrics, such as fuel economy and environmental effect, under different load situations. The study’s findings are encouraging. The study reveals that disabling a specific group of cylinders while permitting unrestricted air intake might result in significant improvements in fuel economy, anywhere from 1.5% to 10.5%, depending on the engine’s workload. Bench testing revealed a maximum improvement of 10.8%, which demonstrates the efficacy of this strategy. The study’s findings indicate that the use of the integrated power regulation approach greatly improves fuel efficiency and decreases the impact of the environmental consequences of spark-ignition engines, especially in situations of low load and idling. This technology demonstrates its feasibility as a solution that can be seamlessly incorporated into current engine designs with few adjustments, providing a practical and environmentally responsible option for enhancing vehicle performance. The results indicate that this approach has wide-ranging potential uses in the automotive sector, particularly for urban cars that often function in situations with modest levels of demand. By using this approach, manufacturers may attain enhanced fuel efficiency and diminish emissions, this contributing to the development of more sustainable urban transportation options.

The article considers ways to evaluate the influence of various implementations of the combined method of power regulating of the engine with spark ignition on mechanical losses and fuel economy. The object of research is a method of power regulating of a spark-ignition engine. The purpose of the study is to evaluate different ways to improve the combined method of power regulating of a spark-ignition engine. A theoretical study of various implementations of the combined method of power regulating of the engine with spark ignition. The study took into account the results of previous studies in this area. According to the results of this study, it is established that when the group of cylinders is deactivated with free air intake, mechanical losses can be reduced and fuel efficiency can be improved by 5...11% in comparison with disabling only a fuel supply with unchanged gas exchange system . KEY WORDS: CYLINDER DISCONNECTION, FUEL ECONOMY, POWER ADJUSTMENT

It`s given an analysis of the distribution of wheeled vehicles regarding values of mass specific emissions of pollutants obtained from the results of tests in the European driving cycle (NEDC) the group of 1109 used (second-hand) vehicles of category M1 of various brands (equipped with gasoline engines, which at the time of production were in accordance with federal environmental requirements of the USA), and imported into Ukraine from North America. The analysis included in particular distribution of pollutants specific mass emission vs. total mileage of 3 main vehicle`s brands of tested group consisted mainly of VW, Mazda and Ford. It`s also included statistical frequency distribution of whole tested group and for aforementioned brands individually in comparison with EU (“Euro-5”) and US (T2B5) emission limits, used for type approval and as OBD thresholds, including Ukrainian limits used for second-hand vehicles that does not approved in accordance to EU legislation or within the 1958 Agreement concerning the Adoption of Uniform Conditions of Approval and Reciprocal Recognition of Approval for Motor Vehicle Equipment and Parts. The analysis gives opportunity of comparison of established in tested group of one of the key European, Japan and US manufacturers of passenger vehicles regarding its emission values distribution based on NEDC test procedure results. It`s given the rationale for amending the current procedure for assessing conformity of this category of vehicles (“Approval of the design of vehicles, their parts and equipment”, approved by order of the Ministry of Infrastructure of Ukraine No. 521 dated 17/08/2012), taking into account cancellation at the end of 2018 (according to the Law of Ukraine No. 2612-VIII dated 11/08/2018) of "Euro-5" standards as the minimum requirements for the first registration in Ukraine of used (second-hand) vehicles of heading 8703 of the Ukrainian classification of goods of foreign economic activity. Keywords: wheeled vehicles, passenger cars, emission of pollutants, regulation, setting of norms, certification, import of vehicles from the USA.

The article considers the problem of spark ignition engines low efficiency in low-load and idling modes, as well as one of the ways to solve it by improving the combined method of power control. The object of research is the influence of the power control method of spark ignition engine on fuel efficiency. The purpose of research is to improve the combined method of power control of a spark ignition engine. As a result of familiarization with the previous works which were conducted in this direction, it is established that by deactivating a group of cylinder when engine is idling or at low loads a fuel economy is improving. However, previous works has not considered a possibility of performance improving of engine with electronic control system by filling the deactivated cylinders with exhaust gases of working cylinders, heated air, or a mixture of exhaust gases and air. KEY WORDS: CYLINDER DISCONNECTION, FUEL ECONOMY, POWER ADJUSTMENT.

Analysis of normative-and-legal documents related to calibration of measuring devices and testing equipment was conducted; a methodology with an example of calculating between-calibration period was proposed; some issues of its optimisation were considered. Keywords: calibration, between-calibration period, methodology, calculation, determination.