250 HPDI choking at high rpms

[BassCrazy]

’03 Yamaha 250 Vmax HPDI. When I get to WOT the motor acts like it wants to choke out. rpms drop by 1000/1200. It runs great trimmed out at 5000 rpms, but when I move to wide open after a minute it starts to skip/choke. It's not the prop it has been off and on again. It's not trimmed too high, it does it at WOT with the bow down at 5000 rpms. I have replaced the fuel filter and added a water separator, no help. Any ideas would be appreciated. Oh, new plugs also.

[boats.net]

You need to take it to a dealer and see if it has the updates done to it , it may have the old style ign. coils on it.