I have a 2005 50 HP four stroke EFI with about 25 hours on it that has suddenly developed a rough idle-lack of RPM problem. The engine ran perfectly last week. This weekend it started right up, but was idling very rough. I figured it might have some contaminants in the fuel and would work itself out under throttle/load, and did smooth out at 1500 RPMs, but would not pass 4000 RPM at WOT. Usually turns about 5600-5800 at WOT. Have checked all the obvious potentials and added a can of seafoam to the system, but still have the issue. Would greatly appreciate any thoughts. Thanks for your time.
