FUEL SYSTEM CONTROL

摘要

Methods and systems are provided for accurately confirming fuel tank depressurization before unlocking a fuel door to enable refueling. Following a refueling request, a fuel system may be sealed from the atmosphere while one or more fuel system valves are adjusted to divert fuel tank pressure or vacuum to an engine intake. Depressurization may be inferred based on the presence of air or vapor flow into the intake as sensed by a manifold airflow sensor.

主权项

1. A method for a hybrid vehicle, comprising:
during refueling conditions, directing fuel tank vapors from a sealed fuel system to an engine intake manifold; and indicating depressurization of a fuel tank based on output of a mass air flow sensor.