Abstract: Disclosed is a method for establishing an engine maintenance diagnosis. The engine includes a throttle which regulates air access into an air intake system of the engine, a position sensor which measures the position of the throttle, a manifold in fluidic communication with the throttle, a pressure sensor which measures the pressure in the manifold, at least one intake valve, a richness probe which measures an oxygen level and a richness controller for modifying the proportions of air and fuel in the air-fuel mixture. The method uses two air flow measurements in order to identify a problem in the throttle or the play at the valves.

Abstract: A method for controlling an internal combustion engine with a crankshaft position sensor, intake air pressure sensor and fresh air intake throttle valve, includes: determining the engine's rotational speed based on the crankshaft position derivative relative to time; determining the intake air pressure for a first crankshaft position corresponding to 180° before top dead center; determining the intake air pressure for a second crankshaft position corresponding to 390° before top dead center; determining an atmospheric pressure learning pressure threshold based on the engine's rotational speed; determining whether the difference between the intake air pressures for the first and second crankshaft positions is below the atmospheric pressure learning pressure threshold; if so, commanding atmospheric pressure learning by applying a first-order filter to the intake air pressure for the second crankshaft position; and controlling the internal combustion engine as a function of the learned atmospheric pressure value

Abstract: A method for controlling an internal combustion engine with a crankshaft position sensor, intake air pressure sensor and fresh air intake throttle valve, includes: determining the engine's rotational speed based on the crankshaft position derivative relative to time; determining the intake air pressure for a first crankshaft position corresponding to 180° before top dead center; determining the intake air pressure for a second crankshaft position corresponding to 390° before top dead center; determining an atmospheric pressure learning pressure threshold based on the engine's rotational speed; determining whether the difference between the intake air pressures for the first and second crankshaft positions is below the atmospheric pressure learning pressure threshold; if so, commanding atmospheric pressure learning by applying a first-order filter to the intake air pressure for the second crankshaft position; and controlling the internal combustion engine as a function of the learned atmospheric pressure value