again thank you very much DGS
the 2001 02 03 motor did have the fuel pressure regulation on the fuel rail and did run off manifold vacuum
in 2004 fuel pressure regulation was remover from the fuel rail and installed in the fuel filter
the fuel re-tune line was all so remover and the case for the fuel pressure regulation is empty
this is why you see the manifold vacuum line caped off
2 pics are 1 with and 1 with out the fuel pressure regulation
81xvHPo+8GL._SL1500_.jpgs-l1600.jpg
BUT this setup does let the fuel set at the motor and gets warm . but never hot . my setup runs cool
what i cant test for is to see if there is air in the line like if there is a pin hole on the vacuum side of the fuel pump
but the misfires are when the system is cold and go away more when it gets up to temp .
thats why i think some of my fuel tabs are off for lower temps or idle