25 el rpm and starting problems

[widowmaker1]

I have a 2001 25 EL , yesterday it wouldn't start unless you throttle it up some, then it will rev up fine ,but when you put it in gear and run it under preassure it will only run at half rpm's and sounds baffled. I changed the spark plugs and cleaned the carb to no avail. Any help wopuld be greatly appreciated. This motor doesn't have that many hours on it.

[boats.net]

Check to see if firing on all cylinders.

[widowmaker1]

it is firing on both cylinders ,when i pull a spark plug wire off it starts skipping.

[boats.net]

Sounds like carb still has plugged jets or passages.