METHOD AND DEVICE FOR DETECTING AUTO-IGNITIONS IN A SPARK IGNITION INTERNAL COMBUSTION ENGINE

摘要

In a spark ignition internal combustion engine having a plurality of cylinders (Zyl (x)), successive segment time periods which are assigned to the individual cylinders(Zyl (x)) and which the crankshaft requires during the working strokes of the cylinders (Zyl (x)) in order to run through predefined angle ranges are measured, and subsequently irregular running values (LU_Zyl (x)) are determined from the segment time periods. In a predefined load/rotational speed range of the internal combustion engine, the irregular running values (LU_Zyl (x)) of all the cylinders (Zyl (x)) are compared with a predefined threshold value (LU_Zyl_SW), and suspected auto-ignition for a cylinder (Zyl (x)) is detected if the irregular running value (LU_Zyl (x-1)) of a cylinder (Zyl (x-1)) located before the cylinder (Zyl (x)) in terms of the timing of the ignition sequence undershoots the threshold value (LU_Zyl_SW). The supply of fuel to the cylinder (Zyl (x)) suspected of having auto-ignition is interrupted for a predefined number of cycles (z), and the influence of the interruption of fuel into the cylinder (Zyl (x)) on the irregular running values (LU_Zyl (x-1)) of the cylinder (Zyl (x - 1)) during the cycles (z) is detected. The suspected auto-ignition of the cylinder (Zyl (x)) is either confirmed or rejected as a function of the irregular running values (LU_Zyl (x-1)) occurring at the cylinder (Zyl (x-1)).