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Operability and efficiency of transport diesel engines significantly depend on periodical diagnosis of its technical condition. The article considers the features of monitoring and diagnostic of transport diesel engines with the help of vibroacoustic analysis of high pressure fuel equipment and gas distribution mechanism. Functional scheme of diagnostic system and analytical method of TDC determination is described. Article gives an example of four-stroke and two-stroke diesel engines diagnosis. Also the article shows turbocharger speed determination and diagnosis with the help of vibroacoustic spectrum analysis. The main feature of the given methods is their high efficiency for diagnosis of transport diesel engines during operation.

The article deals with experimental and theoretical researches of hydraulic processes in a system of accumulator fuel supplying (Common Rail) during the diagnosing while the vehicle idling and during the acceleration. The aim of the work is to assess the efficiency of the offered diagnosing technique as the point of view of cutting-down time for troubleshooting and as the point of view of increasing reliability of failure localization. Feature of the presented approach is that it uses the analysis of fuel pressure fluctuations in the high pressure hydroaccumulator, synchronously with the analysis of rotary speed of an engine crankshaft and the steering signals on electromagnetic magnets (or piezoelements) of injectors. The technique uniting preliminary diagnosing of Electronic Engine Control (EEC) and components of the vehicle fuel units during the constant remote monitoring process, and deep, detailed diagnosing at a service station is described.

The article discusses the features of designing a diagnostic system in which harmonic analysis is used to improve the quality of diagnostic information processing. The cyclic analog signal coming from the sensor and containing the diagnostic information is converted into a discrete signal. Accumulation of diagnostic information processed by equipment is carried out in the form of discrete signals. The processing and analysis of the obtained diagnostic information is carried out by applying harmonic analysis. Periodic processes of operation of vehicle units are associated with the occurrence of noise and vibration having a different frequency but related to the same node. A feature of the presented system is that it uses a contactless method of obtaining diagnostic information about the operation of vehicle units. The system calculates the speed of the node, measures the noise level and calculates the level of vibration that occurs during its operation.

Diagnosis of the car is a necessary means for early detection of developing malfunctions. A technique for diagnosing on a short road based on the acceleration in the second and third gears and coasting from 50 or 40 to 20 km/h is proposed. The results should be compared with the reference values calculated, taking into consideration the speed rolling resistance dependence, described by the square trinomial, the speed air resistance dependence with the variable exponent, the losses of the transmission idling mode and the progressive total resistances decrease at speeds below 25 km/h. The general speed dependence of the total resistance is described by a sixth-degree polynomial but not the second-degree one, as many researchers believe. The experimental check was performed on a subcompact sedan with 1.6 atmo engine. Weight of 1370 kg. First class road with an average rise of 0.0182, asphalt in good condition. There was no wind.

The paper describes the process of modeling and optimizing the operating conditions of vehicles for a section of the transport network using simulation tools. The cyphergrams of the transport flow intensities in the transportation hub were built, a graphic model of vehicle traffic in the transportation hub was built, and a transition probability matrix was compiled, which was used to simulate modeling and optimize vehicle operating conditions for the considered transport hub. It is necessary to use simulation modeling software that supports all simulation methods and a powerful built-in library for traffic modeling. The corresponding simulation model was created. With the help of it, modeling in the transport hub selected for research has been carried out and the optimum values of the duration of the phases of traffic light objects have been obtained. It has reduced the average travel time through the site, which is considered in the work, and the number of cars in traffic jams.

Thermal control of a vehicle engine operation is a key aspect of the development of a vehicle warming-up systems. The use of heat accumulators and phase transition heat-accumulating materials is perspective. The given article describes the ways of improving thermal properties of phase transition heat-accumulating materials in the processes of their designing, the efficient ways of heat transfer from phase transition heat-accumulating materials to heat carrying agent of heat accumulators and then to vehicles. To create reliable phase transition heat-accumulating materials, different ways of their realization are suggested. One of them is the construction of the corresponding phase diagrams to determine an optimal composition of phase transition heat-accumulating materials with higher thermal properties to operate in a given temperature range.