Patent ID: 11591981

Abstract:
According to the invention, a diagnostic system is provided for diagnosing a misfire condition is provided of individual engine cylinders in a turbocharged diesel engine having at least a first and a second cylinder associated with a common exhaust path. The system comprises a pressure sensor in an exhaust path, for measuring a pressure value; a crankshaft position sensor, for detecting a rotational crankshaft position; and a processor unit for reading the pressure sensor and the crankshaft position sensor. The processor unit is arranged for performing acts of: sampling pressure values of the pressure sensor in the common exhaust path as a function of crankshaft angle position; attributing for each cylinder fired in succession at least two sampling values (Pα, Pβ) for at least two successive crankshaft angle positions of a pressure pulse during a cylinder firing operation; determining a boundary for a coordinate (Pα, Pβ) formed by a tuple of sampling values (Pα, Pβ); diagnosing a misfire condition if the coordinate formed by said tuple of sampling values is outside the boundary.