Patent ID: 6158273
Filing Date: 2000-12-12
Classification: F02D,G01M

Abstract:
A method for detection of at least one of misfiring and unbalance between the cylinders of an internal combustion engine, said method comprising the steps of:using a torque sensor mounted on a crankshaft of an internal combustion engine to measure a torque of said internal combustion engine and generate a torque signal therefrom;sampling said torque signal speed-synchronously;performing a weighted averaging of the torque signal with a weighting function which cancels or damps an influence of sinusoidal variations of said torque signal with frequencies equal to a selection of integer or half-integer multiples of a speed of said internal combustion engine;wherein:said selection of speed multiples is substantially dependent on a number of cylinders of the internal combustion engine; andsaid detection is based on a result of said averaging.