Service Warning alarm SPN: 65597 FMI:7 system not responding properly

[Swingingbridge]

Have been getting this service warning: Service Warning  with an active engine fault code of SPN: 65597 FMI:7 system not responding properly. Know it has something to do with cylinder 7 misfire but can’t diagnose problem. Changed spark plugs, swapped wires to different cylinder, swapped direct to cylinder ignition distributor modules. Boat has Monsoon 409 6.0 l engine which has direct cylinder ignition modules. Still coming up with same active engine fault so can’t be plugs wires or ignition module then because code didn’t switch after I swapped parts. Boat runs smooth with no load but with a load on engine can’t get above 9.5 mph with full ballast at full throttle. Anybody have any recommendations I am out of ideas. Thank you.

[hunter77ah]

Could it be bad gas or a clogged injector?

[Swingingbridge]

Thanks Going to try swapping injectors tonight to see if the error code changes to that cylinder. Gas is always fresh and new from good supply. 

[Rich777]

Did you ever figure out your issue? I have same thing going on with mine right now