It is hard to judge the condition of a seadoo pump liner because it is plastic and wears on different sections. Pull it out and inspect it. You may find it could be worn. Sealing up all orifices before the impeller with sikaflex will reduce cavitation. Also a WORX, RIVA or R&D scoop grate will improve hole shot. Also a skat trak or solas impeller will improve overall performance.