Engine start fuel control system

An engine startup fuel control system for use with an internal combustion engine of the type having at least one combustion chamber, an intake air passage fluidly connected each combustion chamber, a cold start fuel passageway having an inlet and an outlet, the cold start fuel passageway outlet being fluidly connected to the combustion chambers and a source of fuel, said fuel control system comprising:

• a crankshaft position sensor which generates an output signal representative of the angular position of the crankshaft,
• a camshaft position sensor which generates an output signal representative of the angular position of the camshaft,
• a multipoint fuel injector associated with each combustion chamber, each multipoint fuel injector having an inlet connected to the fuel source and an outlet fluidly connected to said intake air passageway adjacent its associated combustion chamber, each said multipoint fuel injector, upon activation, injecting fuel into its associated combustion chamber,
• a cold start fuel injector having an inlet connected to said fuel source and an outlet fluidly connected to the inlet of the cold start fuel passageway, said cold start fuel injector, upon activation, introducing a fuel charge into the inlet of the cold start fuel passageway,
• processing means programmed to calculate the amount of fuel to achieve a predetermined air/fuel mixture for each cylinder and to determine the synchronization following initiation of camshaft rotation of the engine in response to said output signals from said camshaft sensor and said camshaft sensor and for producing said programmed air/fuel combustible charge in each combustion chamber during engine startup by selective activating said multipoint fuel injector during engine startup and after engine synchronization to provide fuel to each combustion chamber sufficient to compensate for any transport delay of the fuel charge from the cold start fuel injector through the cold start fuel passageway.

A method for managing fuel delivery in an internal combustion engine having multiple combustion chambers during engine startup, said engine having a crankshaft, a camshaft and a multipoint fuel injection associated with each combustion chamber, said method comprising the steps of:

• determining the angular position of the crankshaft after initiation of crankshaft rotation,
• determining the angular position of the camshaft,
• thereafter calculating the required activation of the multipoint fuel injectors to achieve a predetermined air/fuel mixture in each said combustion chamber as a function of the angular position of said crankshaft and crankshaft, and
• thereafter selectively activating said multipoint fuel injectors in response to said calculating step to achieve said predetermined air/fuel mixture in each said combustion chamber.