Cycle to cycle variation of a spark ignition engine is analyzed utilising wavelet analysis technique based on the spectral-temporal approach to stabilizing high cyclic variations. The selected examples of previously published cyclic IMEP measurements from a DISI engine a different percentage of fusel oil blended with gasoline (FAWE10, FAWE20, FBWE10 and FBWE20) under 4500 rpm engine speed and 60% WOT are studied. The results reveal that the increase in spectral power is observed with increasing fusel oil up to 20% with both blends (FBVVE20 and FAWE20). The indicates a pronounced influence of fusel oil ratio on the engine CCV of IMEP. However, the maximum peak in GWS observed for FBVVE20 fuel blend with more uniform overall spectral power for FAWE20 fuel blend which indicates a noticeable enhancement in cyclic variations behaviour after water extraction. As an outcome, the fusel oil water content has acted negatively to restrict the combustion as the fusel oil increased as well as the cyclic variations affected despite the high oxygen content and octane number of fusel oil.