Abstract: A method of controlling knocking in an internal combustion engine equipped with a device for controlling the opening of inlet valves; the control method includes the phases of: determining the occurrence of an excessive knocking in the cylinder of the internal combustion engine; and decreasing the mass of air sucked into the cylinder in which an excessive knocking has occurred by acting on the control device controlling the inlet valves of the cylinder.

Abstract: Control method in the case of a fault in an internal combustion engine; the control method provides for the phases of: cyclically checking the correct functioning of a connection between an electronic control unit and an electric drive of an electric actuator coupled to a butterfly valve to control the position of the same butterfly valve, switching off the electric drive in the case of interruption in the connection between the electronic control unit and the electric drive so that the butterfly valve sets itself in a predefined limp-home position, and piloting the engine in the case of interruption in the connection between the electronic control unit and the electric drive to keep the number of revs constant and equal to a predefined emergency value.

Abstract: A method of controlling an internal combustion engine having at least one cylinder defining a variable-volume combustion chamber; and a rotating crankshaft powered by a piston sliding inside the cylinder; the control method including the steps of: determining a recording window expressed in engine angle degrees and having a start engine angle and a stop engine angle; acquiring and memorizing the intensity of sound pressure waves, generated by the internal combustion engine as a function of an engine angle, by means of at least one sound pressure sensor and within the recording window; and estimating the value of at least one operating parameter of a part of the internal combustion engine by analysing the intensity of the sound pressure waves in the recording window.

Abstract: Control method in the case of a fault in an internal combustion engine; the control method provides for the phases of: cyclically checking the correct functioning of a connection between an electronic control unit and an electric drive of an electric actuator coupled to a butterfly valve to control the position of the same butterfly valve, switching off the electric drive in the case of interruption in the connection between the electronic control unit and the electric drive so that the butterfly valve sets itself in a predefined limp-home position, and piloting the engine in the case of interruption in the connection between the electronic control unit and the electric drive to keep the number of revs constant and equal to a predefined emergency value.

Abstract: Control method for a vehicle with an engine in the case of a fault that advises/imposes driving the vehicle with reduced performance; the control method provides for the phases of: diagnosing the fault, limiting the maximum performance of the vehicle by degrading the performance of an engine of the vehicle and giving the driver of the vehicle advance warning of the imminent operation of performance degradation on the engine before effectively degrading the performance of the engine.

Abstract: A method for detecting misfiring in an internal combustion engine by analysing the angular acceleration of the drive shaft, in which the value of the angular acceleration is estimated at predetermined angular positions of the drive shaft, the absolute value of the angular acceleration is compared with a predetermined threshold value, and the presence of a misfire is detected if the absolute value of the angular acceleration is greater than the predetermined threshold value; when the presence of a misfire is detected, a set of values of the angular acceleration subsequent to the value of the angular acceleration at which the misfire has been detected is filtered to eliminate the oscillation component generated by the misfire with respect to the value of the angular acceleration.

Abstract: Method for finding the angular acceleration of a drive shaft of an internal combustion engine by means of a gear wheel integral with said drive shaft; the method making provision to identify, in each complete revolution of the drive shaft, a number of angular measurement lines, to measure the time used by the drive shaft to pass over each angular measurement line using the signal supplied by the gear wheel, to add algebraically, to the time used by the drive shaft to pass over each angular measurement line, a corresponding correction coefficient that takes account of any asymmetries in the gear wheel, and to determine the value of angular acceleration of the drive shaft as a function of the time used by the drive shaft to pass over each angular measurement line; the value of the correction coefficients is determined in the course of an engine fuel cut-off phase.

Abstract: Method for finding the angular acceleration of a drive shaft of an internal combustion engine by means of a gear wheel integral with said drive shaft; the method making provision to identify, in each complete revolution of the drive shaft, a number of angular measurement lines, to measure the time used by the drive shaft to pass over each angular measurement line using the signal supplied by the gear wheel, to add algebraically, to the time used by the drive shaft to pass over each angular measurement line, a corresponding correction coefficient that takes account of any asymmetries in the gear wheel, and to determine the value of angular acceleration of the drive shaft as a function of the time used by the drive shaft to pass over each angular measurement line; the value of the correction coefficients is determined in the course of an engine fuel cut-off phase.

Abstract: A method for detecting misfiring in an internal combustion engine by analysing the angular acceleration of the drive shaft, in which the value of the angular acceleration is estimated at predetermined angular positions of the drive shaft, the absolute value of the angular acceleration is compared with a predetermined threshold value, and the presence of a misfire is detected if the absolute value of the angular acceleration is greater than the predetermined threshold value; when the presence of a misfire is detected, a set of values of the angular acceleration subsequent to the value of the angular acceleration at which the misfire has been detected is filtered to eliminate the oscillation component generated by the misfire with respect to the value of the angular acceleration.

Abstract: A system for diagnosing a driver and detecting circuit anomalies therein includes: voltage comparator circuits for generating diagnostic logic signals, each of which indicates the existence of a corresponding type of anomaly; and a coding circuit to receive the diagnostic logic signals and to output information relating to an overall operating state of the driver. The coding circuit includes a first portion to provide at its output first logic input signals indicating the last anomaly to occur since a system reset operation. The coding circuit also includes a second portion for coding the first logic input signals. The second portion includes a sequential logic network to receive the first logic input signals and at least one second logic signal indicating the current operating phase of the driver. The second portion provides, as a function of the first and second logic signals, a stable internal state to determine the output information in the form of an N bit coded word.

Abstract: The method of diagnosis determines the state of deterioration of an exhaust gas stoichiometric composition sensor placed downstream of a catalytic converter. The catalytic converter is mounted on an exhaust manifold of an internal combustion engine supplied with an air/fuel mixture, while the sensor generates an output signal correlated with the stoichiometric composition of the mixture. The method comprises the phases of registering a temperature signal correlated with the temperature of the engine; determining the operating range of the engine; determining the stoichiometric composition of the air/fuel mixture; and effecting a hot diagnosis should the temperature signal be greater than a preset reference value, the engine be in the idle operating range and the sensor register a weak stoichiometric composition of the mixture. The hot diagnosis comprises the phases of generating control signals for the engine and of gauging the output signal from the sensor.

Abstract: An electronic concentration control system in which a first exhaust gas composition sensor located in an exhaust pipe downstream from a catalytic converter is connected to an input to a P.I. circuit which generates a control output signal comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor located in the exhaust pipe upstream from the catalytic converter generating a signal which is fed to a proportional integral circuit whose integrating and multiplying coefficients are altered on the basis of the control signal. The system includes a diagnostic circuit which checks the efficiency of the first and second sensors.

Abstract: An electronic concentration control system in which a first exhaust gas composition sensor located in an exhaust pipe downstream from a catalytic converter is connected to an input to a P.I. circuit which generates a control output signal comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor located in the exhaust pipe upstream from the catalytic converter generating a signal which is fed to a proportional integral circuit whose integrating and multiplying coefficients are altered on the basis of the control signal.