1. Field of the Invention
This invention relates to a method and apparatus for the control of an internal combustion engine having means for controlling the amount of fuel supplied to the engine and including at least one cylinder adapted to intake, during each intake stroke of the cylinder, fuel supplied in a plurality of instalments.
2. Description of the Prior Art
In internal combustion engines equipped with a fuel injection system of the type producing, in synchronism with engine rotation, simultaneous fuel injection for all of the cylinders, each cylinder intakes the fuel injected in a plurality of instalments during an intake stroke of the cylinder. The amount of fuel injected for a duration of fuel injection is determined by sensing selected engine operating conditions such as, for example, engine speed and intake airflow and calculating the amount of fuel required for the engine in terms of the sensed engine operating conditions. In the acceleration and deceleration modes of engine operation, however, rapid changes occur in such engine operating conditions to produce a deviation between the required fuel amount and the amount of fuel actually supplied to the cylinder. This creates an overlean air-fuel mixture resulting in poor acceleration power and engine stalling or an overrich air-fuel mixture resulting in increased exhaust emissions and possibly backfire.
The present invention provides a method and apparatus suitable for use in an internal combustion engine having at least one cylinder adapted for intaking, during each intake stroke of the cylinder, fuel supplied in a plurality of instalments to eliminate engine operating instabilities particularly in the acceleration and deceleration modes of operation, thereby producing equilibrium conditions of engine operation at all times.