LOAD DETECTING METHOD, CONTROL METHOD, IGNITION TIMING CONTROL METHOD AND IGNITION TIMING CONTROL APPARATUS FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a load detecting method for an internal combustion engine mountable on a compact car by dispensing with a throttle position sensor and a negative pressure sensor and dispensing with the mounting space for these sensors and the installation of a mounting structure on a vehicle body side. SOLUTION: In a spark ignition engine, an engine load is detected based on a degree of revolution fluctuation of a crankshaft. It is preferable to correct the engine load according to a revolution speed of the engine. The degree of revolution fluctuation is calculated by using a ratio (t/T), wherein t is a passing time of a predetermined fixed angle range of a rotor integrally rotating with the crankshaft, and T is a period of the rotation of the rotor. For example, a difference or a ratio in the ratio (t/T) every rotation or every second rotations of the crankshaft can be defined as the degree of revolution fluctuation.