low fuel pressure merc 115 4 stroke

[EVANDUDE]

I have a '04 merc. 115hp 4 stroke that began losing power over about a 1 month period. Fuel pressure per the manual should be 41psi after fuel pressure regulator. Only getting 23. When I pinch off return line pressure bumps up to 60psi. Sounded like fuel pump was good and regulator bad. Put on new reulator, same story. Any suggestions??

[JUST-IN-TIME]

have u checked all fuel lines
could be in fuel rail