Abstract: Disclosed is a method for determining a static flow rate of a piezo-electric injector of an injection system. The piezo-electric injector includes a needle and a piezo-electric actuator designed to control a valve of the injector. The injection system includes an electric generator designed to send electric current pulses to the piezo-electric actuator of the injector, and a voltage sensor designed to measure voltage values at the terminals of the piezo-electric actuator. The method includes the following steps: sending during a phase of closure of the needle of an electric current pulse such that the piezo-electric actuator is positioned in contact with the valve, without giving rise to the opening thereof; measurement of a plurality of voltage values of the piezo-electric actuator; and determining a static flow rate of the piezo-electric injector on the basis of a plurality of voltage values measured of the piezo-electric actuator.

Abstract: Disclosed is a method for discharging the pressure in a fuel supply rail of an injection system of an engine, the fuel injection rail connected to a fuel tank by piezo-electric injectors, each including a needle and a piezo-electric actuator pressing on a servo valve of the injector. The injection system includes a fuel pressure sensor and an electrical generator transmitting electric current pulses to each actuator. When the accelerator is released, a first electrical command allows determination of a moment of opening of the respective servo valve without triggering an injection. A second electrical command triggers a discharge of fuel from the fuel supply rail to the tank and therefore to discharge the pressure of the supply rail without triggering an injection. The second electrical command charges the piezo-electric actuator between a first voltage level that opens the servo valve, and a second voltage level triggering an injection.

Abstract: Disclosed is a method for determining a static flow rate of a piezo-electric injector of an injection system. The piezo-electric injector includes a needle and a piezo-electric actuator designed to control a valve of the injector. The injection system includes an electric generator designed to send electric current pulses to the piezo-electric actuator of the injector, and a voltage sensor designed to measure voltage values at the terminals of the piezo-electric actuator. The method includes the following steps: sending during a phase of closure of the needle of an electric current pulse such that the piezo-electric actuator is positioned in contact with the valve, without giving rise to the opening thereof; measurement of a plurality of voltage values of the piezo-electric actuator; and determining a static flow rate of the piezo-electric injector on the basis of a plurality of voltage values measured of the piezo-electric actuator.

Abstract: Disclosed is a method for estimating a level of corrosion of an injector of an engine, the engine including a reference injector and at least one other injector, each injector including a tip in fluidic communication with a combustion chamber specific to each of the injectors, the respective combustion chamber of each injector also being in fluidic communication with an exhaust system of the engine. The method includes: while the engine is stopped, inhibiting a propagation of the gases from the exhaust system toward the tip of the reference injector; determining a static flow rate of an injector and a static flow rate of the reference injector; and estimating a level of corrosion of the injector by comparing the static flow rate of the injector with the static flow rate of the reference injector.

Abstract: Disclosed is a method for discharging the pressure in a fuel supply rail of an injection system of an engine, the fuel injection rail connected to a fuel tank by piezo-electric injectors, each including a needle and a piezo-electric actuator pressing on a servo valve of the injector. The injection system includes a fuel pressure sensor and an electrical generator transmitting electric current pulses to each actuator. When the accelerator is released, a first electrical command allows determination of a moment of opening of the respective servo valve without triggering an injection. A second electrical command triggers a discharge of fuel from the fuel supply rail to the tank and therefore to discharge the pressure of the supply rail without triggering an injection. The second electrical command charges the piezo-electric actuator between a first voltage level that opens the servo valve, and a second voltage level triggering an injection.