Abstract: An apparatus for measuring parameters of work diagram of piston machines comprises, connected to one another, a current crankshaft rotation angle counter having inputs coupled, via a crankshaft angular position pulse former and a top dead center pulse former, to an angular mark sensor, and a decoder decoding top dead center signals. To the latter is coupled an input of a flip-flop of an analysis and control unit which also has a counter having an input coupled, via a main coincidence gate, to one of n pressure sensors in cylinders of piston machines, in accordance with the cylinder selected for indication, and a logical circuit having an input coupled to a reversible counter connected to a flip-flop. The apparatus also comprises a series circuit including a decoder for decoding bottom dead center signals coupled to the reversible counter and flip-flop, a cycle length counter and a main flip-flop coupled to the bottom dead center decoder and to an AND gate.

Abstract: An automatic device comprises a complex plane analyzer of a vibration signal of a measured engine unit, electrically coupled via a switch to a computer. The device also comprises a synchronization unit whose inputs are connected to sensors of the angular position of the vehicle engine shaft and transmission shaft, an ignition sensor and a sensor of fuel injection to the cylinders of the vehicle engine. A control input of the unit is coupled to the output of a control unit. There is also an operational parameter measuring unit connected by its inputs to outputs of the synchronization unit and to the output of the control unit. An engine shaft rotational frequency adjustment unit is connected by its input to the control unit and to the synchronization unit and by its output to the actuator controlling fuel supply to the engine cylinders.