METHOD FOR CONTROLLING AN INTERNAL COMBUSTION ENGINE SYSTEM

A method for controlling an internal combustion engine system so as to avoid turbo surge and/or shorten power cut off during gearshift is provided. The internal combustion engine system includes: an internal combustion engine and a gearbox operatively connected to the internal combustion engine; a turbocharging arrangement configured to provide a boost pressure of air fed to the internal combustion engine; and a control system configured to control operation of the internal combustion engine system, the method comprising: providing information about a point of time for initiating an upcoming gearshift, a target engine speed after the upcoming gearshift, iii) a target engine torque after the upcoming gearshift, and current operation conditions of the internal combustion engine system; determining, based on said information and before the upcoming gearshift is initiated, whether there is a risk of having turbo surge during the upcoming gearshift; and, if such a risk is determined, lowering the boost pressure before initiating the upcoming gearshift.