SYSTEMS AND METHODS FOR A VEHICLE ENGINE FUEL SYSTEM

Methods and systems are provided for a vehicle engine fuel system. In one embodiment the method comprises indicating degradation of each of a low-pressure fuel pump and a fuel filter based on a comparison of a pressure differential between a high-pressure pump pressure setting to an actual pressure and a demanded fuel flow to an engine, the indication distinguishing between pump ageing and filter degradation. The method may include adjusting operation of the low-pressure fuel pump in response to the comparison of the high-pressure pump pressure setting and pressure of fuel entering a high-pressure pump. In one example, the fuel filter may be positioned to filter fuel drawn from a fuel tank before entering the low-pressure fuel pump.