Patent ID: 7945371

Claim:
A method for determining a pressure value for the ambient air of an internal combustion engine of a motor vehicle, with the internal combustion engine being designed as a turbocharged engine with a controllable induction tract which, viewed in the direction of flow of the aspirated combustion air, has a charger, a charge-air sensor and a throttle valve in series in that order, with the charge-pressure sensor detecting a charge pressure generated by the charger, that the method comprising the steps of: to determine the ambient pressure, the internal combustion engine is first in a supercharged engine operation, when a negative load step occurs at which the internal combustion engine switches from the supercharged engine operation to a non-supercharged engine operation, measuring the charge pressure and recording the transient profile of the charge pressure and determining a value of a current ambient pressure from the transient profile of the charge-pressure.