Need help with Mercury optimax

[cblazer]

My problem is I have lost about 7mph on top end and my hole shot is gone when my livewells are full. My boat is 21ft long with a 225 optimax. Never had this problem before until this year. I have changed the plugs put a new ignition coil on one cylinder that the computer showed bad at the dealer. Still no luck. Would appreciate any info.

[IFISH2]

Have you had your fuel/air pressure checked? Also make sure all your wiring on the engine with bullet connectors are plugged in securely. I had a temp sensor connector come un plugged and had the same symptoms. Seemed like it was running on 5 cyl. Check compression or maybe your pulse fuel pump diaphragm. Also check your battery connections/terminals for corrosion. I takes lots of juice for the opti's to perform