Abstract: A method for operating an engine includes, but is not limited to acquiring a value of at least one engine operating parameter, using the set of values for determining a predicted value of a combustion parameter indicative of fuel combustion performance within an cylinder, using the values as input of a data-set returning as output a correlated correction value of the combustion parameter, using the correction value and the predicted value for determining an expected value of the combustion parameter, feed-forward controlling an injection of fuel into the engine cylinder targeting the expected value of the combustion parameter, measuring a value of the combustion parameter within the cylinder due to that injection of fuel, using a difference between the expected value and the measured value of the combustion parameter for correcting the correction value of the data-set that is correlated to the set of engine operating parameter values.