Fuel issue

I have a 2005 115 4 stroke , it starts, idles, lit ruff , when put load on it, gives out, like its sucking air.? checked filter for water , checked in line filter, plug, ??
Can someone tell me how to check file psi and what psi's I should have. I rigged up a gage but didn't work, at the top of the injection rail there is a vale steam like a car tire has. I'm guessing this is where I can check it?

[boats.net]

Should have 44 psi at schrader valve on VST.

Should have 44 psi at schrader valve on VST.

Is that at idle or check it while moving?? Is was cutting out last ya, just a little, I out new hose and bubble one it, thought it helped but didn't use it much, this year , it just bogs down when take off, runs OK slow ,but only had it kick in and take off for about a min. then bogged back down??