I have a 1989 Force 85 HP Outboard. Model 856L9B, Ser # 1624. I have had it for two years and it has run well at high rpm but tends to intermittently have an engine miss at idle. Most recently it tends to skip as the throttle is advanced and then it feels like a cylinder comes back on line and goes fine. The carbs have been removed and cleaned and the float levels set. It has new plugs. Spark tests at the plugs shows good spark when cold. It also seems to be worse after the engine warms up. The most recent attempt to set idle speeds resulted in the top cylinder not responding when the throttle was advanced even though the idle was set approximately to the factory recommended setting. After a brief hesitation the cylinder will come on line. Would appreciate any thoughts/suggestions on the problem.