METHODS AND SYSTEMS FOR DUAL FUEL INJECTION

摘要

Methods and systems are provided for reducing fueling errors resulting from pressure pulsations in a port injection fuel rail. The pressure pulsations result from pressure pulsations generated in a high pressure fuel pump delivering fuel to both the port injection fuel rail and a direct injection fuel rail. A center of a port injection fuel pulse is repositioned on a nearest fuel rail pressure sampling point in the advanced direction to improve the accuracy of the delivered fuel pulse.

主权项

1. A method for an engine, comprising:
pressurizing fuel in a port injection fuel rail via an engine camshaft-driven high pressure fuel pump; intermittently sampling fuel pressure in the port injection fuel rail; and during conditions when a port injection fuel pulse is smaller than a threshold, moving the port injection fuel pulse from an initial timing, asynchronous with the intermittent sampling, to a final timing, synchronous with the intermittent sampling.