2005 VZ225TLRD surges at 4000 rpms. The hole shot and acceleration is good to 4000. The surge is violent and rpms drop out drastically. If I accelerate out of the hole and back off before hitting that 4000 mark I can cruise forever without a hiccup. Prior to taking the boat into the dealership I changed the filters and installed new plugs. They hooked up diagnostic unit. It showed no code. They checked fuel and electrical and all they could come up with was small rust like particles in the needle valve inside the VST. It was taken to the lake by them and I was told it ran out fine. I drive 50 miles to pick up. Prior to returning home I took it to the lake. Same issue. Returned to the dealership. They again hooked it up to the diagnostic unit. Now a code shows up for high pressure fuel. They say it's the high pressure fuel pump located inside the VST which they replace. This is an expensive part. I return to the dealership today and again do a lake test before returning home. The dealership didn't have time to do lake test but assured me everything checked out. Once again I have failure at the lake. I returned to the dealership, they were stumped. I took the boat home to use at cruising speed and will return on Monday. Any suggestions or ideas of where to go from here appreciated. I have done business here for years but my patience is thin. I don't think it's right for them to keep throwing parts at my outboard and hope it works at my expense. Does this issue sound electrical or gas related to those in the know? I have owned since new. There are 380 hours. I had some electrical issues 2 years ago and many components were replaced at that time. The motor ran fine last year but started acting up about a month ago.