To calculate a fuel injection time based on PA and PB without using a PA (atmospheric pressure) sensor and a PB (negative intake pressure) sensor.
A base calculation part 60 calculates the rotational variation values of the engine by detecting distances between pulses PLS in those areas set for the exhaust stroke, intake stroke, compression stroke, and combustion stroke of the engine by pulses PLS by a crank pulser 1. The rotational variation values PA and PB are co-related to each other between the areas of the strokes of the engine. The controller also comprises a predictive PA calculation part 65 and a predictive PB calculation part 66 installed for low and high rotational speeds. The calculation parts 65 and 66 calculate PA and PB by using the rotational variation values calculated by the base calculation part 60 in an empirical formula.
Michito Hiraki
Sanji Tanabe