1999 yamaha 60 hp

[<Mike>]

I have a '99 Yammie 60hp on a 16' scout. Now, it idles fast at about 1500 RPM and won't get up on plane on the water. I only get about 2000-2500 RPM in gear at full throttle, but if I put it in neutral, it will rev up to 5500 like normal. At first I thought it might have been condensation in the fuel, but after emptying the h2o/fuel separator bowl and replacing the plugs, as well as putting in a new tank of gas, and checking the carbs (looked pristine) it still does the same thing. Like I said, this thing is intermittent, and if I run it long enough it's like something catches and then I'm back to full power. Any thoughts on what might be ailing my little motor? I have been told that the problem is the microcomputer part # 6h285540-10-00 (now superceeded by part -12-00)

Much obliged

[<boats.net>]

That is an expensive part to do trial and error.
Start with the basic's compression, fire and fuel checks and find problem before changing out parts
It can be any of the three checks you need to know the compression is good before anything. I know Sync. and link is out because that engine should not idle at 1500 RPM's

[<mike>]

I know that the top cylinder isn't getting any fire, as I switched the circuit wires to the cylinders and still the top cylinder was the bad one. Was told that the reason it idles at 1500 is because its shunting fuel to the other 2 cylinders. does this make any sense and does it sound like a new cdi would fix this?