The history of study on stability limit control of gasoline engine was so long and many of them controlled the past cycle combustion fluctuation rate. However, most of the cycles are less than the stable limit fluctuation rate even when the engine is operated near the stable limit. Therefore, if the future cycle fluctuation rate can be predicted, it is considered it becomes possible to extend the lean limit. So, we investigated the specifications of the partial Autocorrelation of IMEP fluctuations. This result showed that the former cycle had significant influence on the next cycle and the proportion of the alternating fluctuations was high. This report shows the method and performance which predicts adaptively the next cycle IMEP fluctuation rate based on the above results.