ljctool

I need help with my honda 03 F12X turbo. The rpms have dropped to 5600 and the top speed has dropped from 61-63 to 56mph .I took it to the honda shop and they said it was to much oil in the engine .I got them to change the oil and filter , I changed the spark plugs ,and added sea foam to the gas ,and still running like crap. It also skips when idling and acts like it is running on three cylinders. I have two of the these and the other one will blow it off the water . The ski has 160 hours on it . Also have sprayed the waste gate with crc,and has never been in salt water. Any help would be appreciated .thanks,Larry