Fuel Pressure Problem

My 2006 Honda BF 225 started giving me trouble toward the end of last season. After trolling for some hours, when starting to rev up to make a move, the engine will start to stutter, like it wants to die. I pull back on the throttle and wait a minute and she will then run fine.

Last year I installed a new VST, because of the drain screw being unable to open and the HP fuel pump. So far I have replaced the fuel lines from the gas tank up to just before the line enters the motor, including a new bulb and replaced the LP fuel pump, all new fuel filters. Yesterday, I removed the right side water relief valve, there was some built up debris in the small tube for the line going to the VST. My next step is to change out the filter on the external water separator.
Checking the fuel pressure yesterday, I get a steady reading of only 34 PSI.
Any thoughts on what can be the reason for the low fuel pressure?
Maybe fuel pressure regulator?
Thanks in advance

First culprits are plugged filter, sucking air or clogged fuel injectors. My bet is injectors.

eneuslis, thanks for the reply. By hooking up the fuel pressure gauge at the VST and getting a reading of 34 PSI at this point, before the fuel rail, be a good indication of clogged fuel injectors?
I am not a mechanic, just trying to understand

Each injector has its own PSI output. With today's fuel if running ethanol based, even with fuel/water separators and inline fuel filters, they are still prone to clog over time with use and years. There are videos on how to clean them yourself on youtube, or there are a few places you can ship them out to be professionally cleaned or full replacement. A clogged injector may not be seen as an issue at idle or low throttle but when you try to get on plane you will see decreased performance from RPM, speed and sometimes a loss of a cylinder.

Update on fuel pressure problem.

I removed the HP fuel pump from the VST and cleaned out the big screen on the bottom of the casing. After placing it back on the engine, I checked fuel pressure and it was still showing 34 PSI. I did a sea trial and the motor ran really well. Still concerned about the low fuel pressure, I removed the fuel rails, cleaned a very little screen at the top of the fuel rail on the port side of the engine, behind the fuel pressure regulator. Removed the injectors and cleaned all of them. Then did a fuel pressure check again, and it read 40 PSI.
I am not sure which of these items that I cleaned was the culprit, could have been both of them creating a reduction of fuel pressure, but am very happy of the outcome.
Going to try and get out for a boat ride today.
Thanks for all the help