| 摘要 |
<p>PURPOSE:To prevent the hunting and to improve the followability of supercharge pressure control by bringing a supercharger into a low supercharge pressure condition when the knocking is occurring while bringing the supercharger into a high supercharge pressure condition when the knocking is not occurring. CONSTITUTION:Under a high supercharge pressure condition where the engine load Q/N is higher than a predetermined level, a solenoid valve 28 is turned on to perform the delay angle correction based upon a first referential level (high correction level). Under a low supercharge pressure condition where the engine load is lower than the predetermined level, the solenoid valve 28 is turned off to perform the delay angle correcting based upon a second referential level (low correction level). If the delay angle correction levels are exceeding over a referential level over more than two rotation zones, it is decided that the octane value of fuel is low and the solenoid valve 28 is turned off. If said levels are lower than the referential level, it is decided that the octane value of fuel is high and the solenoid valve 28 is turned on.</p> |
