i bought a used 2004 le di this spring for $6900 thinking i got a pretty good deal as well. my boat fires right up and runs 53 mph top end but after a while the rpms drop down to about 5000 grand and the boat seams to bog down. i then shut off the engine, let it sit for a minute or so and it then runs good again. what has your dealer done for work on your boat? fuel filter? plugs? supposedly these things have a computer in them that the dealer plugs into. i wish i could give you more advice but i am myself thinking of bringing mine to the dealer.