A method is provided to manufacture a fuel injection control system
controlling fuel injection in an internal combustion engine with a fuel
injection valve. A fuel injection valve is trial-manufactured. Using this
valve, correcting amounts for an injection period are calculated at
plural adjustment points defined by fuel pressures and injection periods.
The adjustment points are divided into actual-measuring points and
predicting points, and the correcting amounts at the actual-measuring
points are used to calculate predicting expressions to predict correcting
amounts at the predicting points and relational expressions to define a
relationship among the correcting amounts at the actual-measuring points.
When the valve is mass-manufactured, for each mass-manufactured valve,
the correcting amounts at the actual-measuring points and the predicting
expressions are used to predict correcting amounts at the predicting
points, providing the correcting amounts at the actual-measuring and
correcting points. Appropriateness of the predicting expressions is also
estimated.