摘要 |
Pinging in an internal combustion engine is avoided by reducing the ignition advance angle, whenever pinging is detected, by a given angular retardation to arrive at a corrected advance angle. In the absence of pinging at said corrected advance angle, the angle of advance is progressively increased again stepwise at a first incremental rate of increase which is being maintained so long as the absence of pinging is maintained, up to a maximum cumulative increase; if this cumulative increase is attained without again detecting pinging the advance angle is increased stepwise at a second incremental rate until the normal advance angle value or the recurrence of pinging. At the time of transition from said first to said second incremental rate, said second incremental rate of increase is greater than or equal to said first incremental rate. |