Spark plug smoldering detection method, internal combustion engine combustion control method, and internal combustion engine combustion control device

摘要

PPROBLEM TO BE SOLVED: To restrain the deterioration in operation performance of an internal combustion engine by detecting smoldering of an ignition plug in a stage before a misfire frequently occurs and resolving the smoldering in that stage. PSOLUTION: A voltage dividing circuit constituted of resistors 38, 39 and condensers 36, 37 is connected to a primary power source line 31 connecting a primary winding 33 of the ignition coil 32, which applies high voltage for ignition to the ignition plug 10, to a battery 26. An A/D converter 44 converting a voltage of electromotive forces applied to the resistor 39 into a digital value and inputting the value to an ECU 21 is provided on a connection part between the resistor 38 and the resistor 39. When spark discharge is performed on the ignition plug 10, a CPU 22 of the ECU 21 determines whether the spark discharge is normal spark discharge or inward flying sparks in accordance with the voltage input from the A/D converter 44, and self-cleaning of the ignition plug 10 is performed as needed. PCOPYRIGHT: (C)2004,JPO&NCIPI