Method for operating a direct fuel injection system

摘要

A method, comprising: during engine cylinder operation with fuel from a first injector and not a second injector: increasing a rail pressure of a fuel rail coupled to the second injector in response to a temperature increase of a tip of the second injector. In this way, by raising the rail pressure of a fuel rail coupled to the second injector in response to a temperature increase of a tip of the second injector, the method may be utilized to prevent a vapor space from forming within the tip of the second injector which is exposed to the heat of combustion within the engine cylinder. By preventing a vapor space from forming, the method may be used to prevent fuel distillation in the tip of the second injector during periods where the engine cylinder is operating with fuel from a first injector and not the second injector.

主权项

1. A method, comprising:
during engine cylinder operation with fuel from a first injector and not a second injector:
increasing a rail pressure of a fuel rail coupled to the second injector in response to a temperature increase of a tip of the second injector greater than a threshold temperature, rail pressure repeatedly increased by repeatedly pumping fuel into the fuel rail via a high pressure fuel pump while maintaining no net flow through the second injector.