2008 225 optimax fuel pump issue??

[davindyson]

I was running at 4800rpms and motor abruptly dropped rpms to 1500..The motor cranks and idles fine,it also has plenty of power up to 1500/1600 rpms.Then when you push throttle forward no response in rpms at all,I replaced screw in castle filter and high pressure pump to no avail.The motor will rev up out of water,I also get no alarms on smartcraft gauges..would a bad lift {diaphragm} pump do this,I do not feel the pulsating fuel coming to the pump like before...Please advise..

[boats.net]

Need to test fuel and air pressure to see if within specs.