Patent ID: 9689329
Date: 2017-06-27
CPC Classifications: F02D,F02M

Claim:
1. A method for failure detection of injectors in an internal combustion engine, including the steps of: measuring a crank angle signal; transforming said crank angle signal into a frequency range using discrete Fourier-transformation; sequentially turning off each of a number of injectors one time; sequentially capturing and storing one time an angle of the harmonic of the 0.5th order of said Fourier-transformed crank angle signal for each said turned off injector; continuously capturing and storing an angle and an amount of the harmonic of the 0.5th order of said Fourier-transformed crank angle signal; continuously comparing said continuously captured amount with a predetermined threshold value and detecting an injector failure if said continuously captured amount exceeds said predetermined threshold value; and comparing said continuously captured angle with said sequentially captured angles stored for each said turned off injector, if said injector failure has been detected, and identifying said failed injector as an injector for which a stored sequentially captured angle corresponds.