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DI08-13 CHANGED BY EFFECTIVE DATE AFFECTED VIN ENGINE CONTROL SYSTEM DI ENG SM - 2004.9 FUEL FLOW CONTROL Main Flow Control The main flow represents the amount of fuel injected into the cylinder during the main injection. The pilot flow represents The total fuel injected during 1 cycle (main flow + pilot flow) is determined in the following manner. : The driver’s demand is compared with the value of the minimum flow determined by the idle speed controller. • When the driver depress the pedal, it is his demand which is taken into account by the system in order to determine the fuel injected. • When the driver release the pedal, the idle speed controller takes over to determine the minimum fuel which must be injected into the cylinder to prevent the enigne from stalling. It is therefore the greater of these 2 values which is retained by the system. This value is then compared with the lower This value is then compared with the flow limit determined by the cruise control. As soon as the injected fuel becomes This valve is then compared with the flow limit determined by the flow limitation strategy. This strategy allows the flow to As soon as the injected fuel becomes higher than the fuel limit determined by the ASR trajectory control system, the The anti-oscillation strategy makes it possible to compensate for fluctuations in engine speed during transient conditions. A switch makes it possible to change over from the supercharge fuel to the total fuel according to the state of the engine. • Until the stating phase has finished, the system uses the supercharged fuel. • Once the engine changes to normal operation, the system uses the total fuel. The main fuel is obtained by subtracting the pilot injection fuel from the total fuel. A mapping determines the minimum fuel which can control an injector as a function of the rail pressure. As soon as the |