04 mcx dies under power

[85mc]

Hi there,
looking for a little insight, I have an 04 x9 with an mcx with 230hrs. A week ago we were comming back from the end of the lake 30mph and the boat started to slow down while under throttle the more throttle I applied the worse it got and began to misfire to the point it would stall. It started right up and would lidle fine so i idled back to the dock. My mc dealer forund a cracked distributer cap and replaced that the rotor and the plugs. It ran great for 5 days and the same thing happned last night. Took it home opened the distributer and found a small crack on the inside at the top. There is no seal around the bottom of the cap is that normal? temp is good, oil pressure is good, fuel is half tank and fresh, any thoughts?
Thanks Grant

[TX.X-30 fan]

Change the fuel pump its bad. I think the thread is fuel pump 101. 100 bucks and an hours labor and done.