Had this problem two times last year and now first three times this spring, all times the same, I'll just do the last one. Boat sat for two weeks, put in water and started right up but I could tell it wasn't sounding as it should, won't get past 1000-1500 rpm under a load, rev it up in neutral and it will miss or not fire all cylinders until a certain rpm range and then it will for a better word or words sound normal at the higher rpm although it is only there for a second or two before i back it off which then it will not idle right and probably die. Restart no problem, this will go on for five minutes or so and then presto after another restart or higher rev up it will be fine at all rpms. Motor will start and run fine rest of the day or day's I'm on the water and never miss a beat or have this problem. Anybody have some direction to point me? Switchboxes? Idle control box? Thanks.