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AssigneeFord Global Technologies, LLC
InventorsDarren Bisaro, David Lee Boggs, Mark William Peters, Stephen Richard Burke, Stephen John Kotre
Estimating the term…
A method of controlling an engine 12 during engine shutdown to reduce evaporative emissions is provided. The method includes a step 50 of shutting off a fuel pump 28 of the engine 12. The method also includes a step 52 of burning off the fuel from a fuel rail 24 in a cylinder 18 of the engine 12 after the fuel pump 28 is shut off. During the burning off of the fuel, a duty cycle of each fuel injector 22of engine 12 is controlled to allow the engine 12 to operate generally cyclically about a predetermined air/fuel ratio. The predetermined air/fuel ratio is preferably stoichiometric. By burning off the fuel in the fuel rail 24 after the fuel pump 28 is shut off, the fuel pressure in the fuel rail 24 is reduced. The reduced fuel pressure in the fuel rail 24results in reduced evaporative emissions from the engine 12.
A method for controlling an internal combustion engine during engine shutdown to reduce evaporative emissions, said engine having a fuel pump supplying fuel through a fuel rail to a fuel injector, said fuel injector communicating with an engine cylinder, said method comprising:
A method for depressurizing a fuel rail in an internal combustion engine during engine shutdown to reduce evaporative emissions, said engine having a fuel pump supplying fuel through said fuel rail to a fuel injector, said fuel injector communicating with an engine cylinder, said method comprising:
A method for controlling an internal combustion engine during engine shutdown to reduce evaporative emissions, said engine having a fuel pump supplying fuel through a fuel rail to a fuel injector, said fuel injector communicating with an engine cylinder, said method comprising:
An automotive vehicle, comprising:
A controller for an engine, said engine having an intake manifold with a mass air flow sensor generating a mass air flow signal responsive to an amount of air flow in said intake manifold, an exhaust manifold with an oxygen sensor generating an oxygen level signal responsive to an amount of oxygen in exhaust gases in said exhaust manifold, and a fuel pump supplying fuel to a fuel injector, said controller being configured to turn off said fuel pump upon a change of state of an engine control signal, said controller being further configured to calculate a commanded air/fuel ratio responsive to said oxygen level signal, said controller being further configured to calculate a commanded fueling level responsive to said mass air flow signal and said commanded air/fuel ratio, said controller being further configured to control a duty cycle of said fuel injector, after said fuel pump is shut off, to allow said engine to operate cyclically about a predetermined air/fuel ratio.
Dependencies are inferred from the claim text.