Any areas of left over debris that is left on the subfloor that exceeds 1/8” must be removed, sanded, or filled prior to installation. The overall floor flatness tolerance is 1/4” over 10’ or 3/16” over 10’, depending on the product you are using. There should be no abrupt height variation. So most likely you can go right over it if no areas are higher than 1/8”. Scrape off the really bad spots including past floor adhesives.