We just purchased a 2009 crownline 4.3 engine. It only has 50 hours on it. Last week we took it out and coved out for a while. When heading back to the marina, the boat would not go over 2000 rpm. A warning beep came on and and did a double beep continually until we stopped. We could get it over 2000 rpm while in neutral. Came home and looked it up and we did the following: Added drive lube, changed fuel filter and cleaned the carburetor. Put it on muffles in our driveway and it ran just fine under load and we thought we fixed the issue. Took it out on the water this weekend and it did the same thing. All gauges and fluids are running just fine with no issues of any kind. Any ideas as to what might be the issue. Again this boat is crownline, 18.5 extreme razor and it is in immaculate shape, never stored outside.