Patent ID: 7849673

Claim:
A method of heating-up and keeping warm an exhaust gas emission control assembly of a motor vehicle with a drive train, containing one transmission, which is powered by an internal combustion engine and at least one second drive unit, the method comprising: setting at least one of a rotational speed and a torque of the internal combustion engine in an operating state which lies outside of an idling operational state in which the engine operates at an idling speed and wherein the at least one of a rotational speed and a torque of the internal combustion engine in the operating state is deviated from at least one of a standard operating values for rotational speed and torque of the operating state which facilitate operation of the internal combustion engine without performing at least one of heating-up and keeping warm of the exhaust gas emission control assembly, and wherein the method further comprises calculating at least one of an optimum engine rotational speed and an optimum torque required for performing at least one of heating-up and keeping warm of the exhaust gas emission control assembly, and utilizing at least one of the optimum engine rotational speed and the optimum torque to facilitate performing of at least one of disengaging the internal combustion engine from the drive train and reengaging the internal combustion engine with the drive train.