Method for estimating the gas pressure in an intake manifold of an internal combustion engine.

The method involves calculating the flow of air in an engine (1) and flow of input air. The flow of the air in the engine is calculated from engine speed and the temperature of the air in an intake manifold (3). The mass of air in an intake circuit is calculated by integrating the difference between the flows. The pressure in the manifold is then estimated from the temperature of the air in the manifold. Independent claims are also included for the following: (a) a device for controlling an internal combustion engine (b) an internal combustion engine.