Method and system for engine control

摘要

Methods and systems are provided for fuel systems including a gaseous fuel. Temporary flow restrictions in the fuel line of a first gaseous fuel may be addressed by temporarily shifting to cylinder operation with a second liquid fuel. Upon resumption of first fuel operation, if the flow restriction persists, a diagnostic code may be set and cylinder operation with the second fuel may be restarted.

主权项

1. A method of operating an engine, comprising:
responsive to a first fuel rail pressure below a rail threshold and a first fuel tank pressure of the first fuel above a tank threshold, alternating fuel injection to one or more engine cylinders from a first, gaseous fuel from a first fuel tank to a second, liquid fuel from a second fuel tank for a duration without refilling the first fuel tank, and then after the duration alternating back to the first fuel only if the first fuel rail pressure has risen above the rail threshold.