My 2013 20hp 4 stroke suzuki in neutral will rev out around 3000 rpm. as it should. The problem is in the water under way it also revs out at 3000 rpm. Cavitation plate is 1 1/2 inches below the stern. Ive tried 4 different pitch props both 3 and 4 blade with the same results. Fuel flow is good with no air leaks and excellent spark. I know there is a rev limiter but have no way of telling its condition without changing it out. I would appreciate any helpful thoughts.