“…As a complex system consisting of a high-pressure oil pump, common rail pipe, electronically controlled injector, and high-pressure fuel pipe, a high-pressure common rail system is susceptible to various failures during operation due to shock and vibration, wear, corrosion, and aging. In recent years, wavelet analysis, empirical mode decomposition (EMD), ensemble empirical mode decomposition (EEMD), [1][2][3][4][5][6][7][8] and other time domain analysis methods have been widely used in the analysis and diagnosis of diesel engine faults. [9][10][11][12] In the field of eigenvalue identification, energy entropy, permutation entropy, singular values, and time-domain features are applied to the extraction of feature parameters.…”