Patent ID: 7516618

Claim:
An air supply control method for a turbocharged engine having an intake manifold ( 20 ) downstream of a compressor of a turbocharger ( 14 ) and an exhaust manifold ( 22 ) upstream of a turbine of the turbocharger ( 14 ), comprising: determining a mass air flow supplied to the engine and/or a pressure in the intake manifold ( 20 ), together with a temperature in the exhaust manifold, wherein a pressure in the exhaust manifold ( 22 ) is determined as a function of the pressure in the intake manifold ( 20 ), an engine speed, and temperatures in cylinders ( 4 ) and in the exhaust manifold ( 22 ), wherein a correction factor dependent on the ambient surrounding pressure is provided, and wherein the pressure in the exhaust manifold ( 22 ) P exh is calculated by a formula: P exh =[A ( T c )* MAP−B ( N, AMP, T exh )]/ C ( T exh ), where A, B and C are predetermined functions, T c is the temperature in the cylinders, MAP is the pressure in the intake manifold, N is the engine speed, AMP is the ambient pressure and T exh is the temperature of burnt gases in the exhaust manifold.