power loss

[sdsmith]

2003 evinrude 225 h.o.
Running the lake this past wkend at about 70 mph, slowed down to take a curve and stepped on the gas only to get no response. Shut it down and tried to take back off but couldn't get above idle speed. In neutral the engine will rev to high rpm but will not under load. Put in new plugs which improved starting and idle but still nothing above idle speed. Any thoughts???

[boats.net]

Run a compression test. Check fuel pressure, check that all cylinders are firing, check for fault codes.