Method and system for estimating fuel system integrity

摘要

Methods and systems are provided for operating a fuel system configured to deliver a gaseous fuel to an engine. While the engine is shutdown, diagnostic routines may be performed to identify fuel system leaks or breaches. When the engine is subsequently restarted, fuel rail pre-priming is adjusted based on the presence of fuel system leaks.

主权项

1. A method for an engine operating on a gaseous fuel, comprising:
indicating fuel system degradation based on a change in each of a fuel rail pressure and a fuel tank pressure over a duration while the engine is shutdown, including if a difference between the fuel tank pressure and the fuel rail pressure is lower than a threshold after the duration; and in response to the indication, disabling pre-priming on a subsequent engine restart.