Abstract: A method for the diagnosis of an air supply circuit supplying air to a burner of an exhaust gas after-treatment system for an exhaust system of an internal combustion engine, wherein the air supply circuit is provided with a pumping device housed along a first duct adjusted by a shut-off valve. The method entails housing a first pressure sensor along the first duct interposed between the pumping device and the burner; housing a second pressure sensor along a second duct out of the burner; acquiring the pressure signals detected by said first and second pressure sensors; and diagnosing faults and/or malfunctions in the air supply circuit depending on the pressure signals detected by said first and second pressure sensors.

Abstract: A method for the diagnosis of an air supply circuit supplying air to a burner of an exhaust gas after-treatment system for an exhaust system of an internal combustion engine, wherein the air supply circuit is provided with a pumping device housed along a first duct adjusted by a shut-off valve. The method entails housing a first pressure sensor along the first duct interposed between the pumping device and the burner; housing a second pressure sensor along a second duct out of the burner; acquiring the pressure signals detected by said first and second pressure sensors; and diagnosing faults and/or malfunctions in the air supply circuit depending on the pressure signals detected by said first and second pressure sensors.

Abstract: Method to control the sealing of a blow-by gas breather circuit of an internal combustion engine, comprising a separator device to agglomerate the particles of finely atomised lubricating oil and to remove the solid particulate particles and having an outlet connected by a pipe to an intake pipe through which the gas purified from the lubricating oil and the particulate flows out and a pressure sensor; the method providing the following steps: acquiring the signal coming from said pressure sensor; filtering the signal coming from the pressure sensor; integrating over time the square of the filtrated signal coming from the pressure sensor; and determining the sealing of the pipe according to the integrated signal which is the combustion energy generated by the internal combustion engine.

Abstract: Method to control the sealing of a blow-by gas breather circuit of an internal combustion engine, comprising a separator device to agglomerate the particles of finely atomised lubricating oil and to remove the solid particulate particles and having an outlet connected by a pipe to an intake pipe through which the gas purified from the lubricating oil and the particulate flows out and a pressure sensor; the method providing the following steps: acquiring the signal coming from said pressure sensor; filtering the signal coming from the pressure sensor; integrating over time the square of the filtrated signal coming from the pressure sensor; and determining the sealing of the pipe according to the integrated signal which is the combustion energy generated by the internal combustion engine.

Abstract: A method detects a “misfire” condition in an internal-combustion engine including a control unit, a driving shaft and phonic wheel that is splined to the shaft and coupled to a sensor. The method comprises steps of: detecting intensity of a signal generated by passage of teeth of the wheel by the sensor, sampling the signal generated by the passage of the teeth, processing the sampled signal by applying a discrete Fourier transform, representing the sampled signal processed by a virtual phasor that represents in a vector form the signal that has been sampled and processed, determining a corresponding theoretical phasor for the virtual phasor that represents theoretical evolution of the signal that has been sampled and processed over time, comparing the theoretical phasor with the virtual phasor, and determining presence of a “misfire” condition by comparing the theoretical phasor with the virtual phasor that represents the signal that has been sampled and processed.

Abstract: A method detects a “misfire” condition in an internal-combustion engine including a driving shaft and phonic wheel that is splined to the shaft and coupled to a sensor. The method comprises steps of: detecting intensity of a signal generated by passage of teeth of the wheel by the sensor, sampling the signal generated by the passage of the teeth, processing the sampled signal by applying a discrete Fourier transform, representing the sampled signal processed by a virtual phasor that represents in a vector form the signal that has been sampled and processed, determining a corresponding theoretical phasor for the virtual phasor that represents theoretical evolution of the signal that has been sampled and processed over time, comparing the theoretical phasor with the virtual phasor, and determining presence of a “misfire” condition by comparing the theoretical phasor with the virtual phasor that represents the signal that has been sampled and processed.

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.