Method and control device for determining reliability regarding misfire determination of cylinders of an internal combustion engine

A control device for determining reliability regarding misfire determination of cylinders of an internal combustion engine, the control device being configured to, for calibration:

• detect a pressure in an exhaust manifold arrangement of the internal combustion engine for a set of operation parameters comprising a certain range of crank angles for a certain engine load and certain engine speed so as to, for an actual cylinder setup of the internal combustion engine, create a pressure sample value pattern for combustion conditions and a pressure sample value pattern for misfire conditions;
• create a template course for each of the thus created pressure sample value patterns, each of said template courses comprising a set of sample points;
• normalize a pressure for the created template courses at a desired crank angle;
• store normalized thus created template courses;
• determine difference values based upon differences between sample points and corresponding detected and normalized pressure values within a desired range of crank angles;
• and
• summarize the thus determined difference values so as to determine whether a predetermined share of the summarized difference values lies above or below a predetermined threshold value so as to determine reliability regarding misfire determination.

A vehicle operated by an internal combustion engine, the vehicle comprising a control device for determining reliability regarding misfire determination of cylinders of the internal combustion engine, the control device being configured to, for calibration:

• detect a pressure in an exhaust manifold arrangement of the internal combustion engine for a set of operation parameters comprising a certain range of crank angles for a certain engine load and certain engine speed so as to, for an actual cylinder setup of the internal combustion engine, create a pressure sample value pattern for combustion conditions and a pressure sample value pattern for misfire conditions;
• create a template course for each of the thus created pressure sample value patterns, each of said template courses comprising a set of sample points;
• normalize a pressure for the created template courses at a desired crank angle;
• store normalized thus created template courses;
• determine difference values based upon differences between sample points and corresponding detected and normalized pressure values within a desired range of crank angles;
• and
• summarize the thus determined difference values so as to determine whether a predetermined share of the summarized difference values lies above or below a predetermined threshold value so as to determine reliability regarding misfire determination.

A non-transitory computer-readable medium used for determining reliability regarding misfire determination of cylinders of an internal combustion engine, said non-transitory computer-readable medium storing computer program code comprising computer instructions to cause one or more control devices to perform the following operations:

• detecting a pressure in an exhaust manifold arrangement of the internal combustion engine for a set of operation parameters comprising a certain range of crank angles for a certain engine load and certain engine speed so as to, for an actual cylinder setup of the internal combustion engine, create a pressure sample value pattern for combustion conditions and a pressure sample value pattern for misfire conditions;
• creating a template course for each of the thus created pressure sample value patterns, each of said template courses comprising a set of sample points;
• normalizing a pressure for the created template courses at a desired crank angle;
• storing normalized thus created template courses;
• determining difference values based upon differences between sample points and corresponding detected and normalized pressure values within a desired range of crank angles;
• and
• summarizing the thus determined difference values so as to determine whether a predetermined share of the summarized difference values lies above or below a predetermined threshold value so as to determine reliability regarding misfire determination.