2000 Mercury Cougar

Engine Performance problem
2000 Mercury Cougar 6 cyl Two Wheel Drive Manual

I am getting a fuel pressure code P0193. The car will start and run smooth up to 1500 RPM's, however anything higher it starts to boag down. I have performed a fuel pressure test at the fuel rail (key on engine off) I hear the fuel pump spinn up up for about two seconds and get a reading of about 20 PSI the book says it should be 37-41 PSI. If I start the engine the reading will jump up to around 30 PSI. I have allso tested the perssure at the fuel filter outlet (New filter) (Key on Engine off) and get about 6 PSI. I have replaced the fuel filter and the fuel pressure regulator($93). Engine compression is good and spark good. I am confussed with the perssure readings I am getting seems like it may be the fuel pump but hate to spend $229 and not have it work. Any suggestions?
April 4, 2009.

The fuel pump is weak-replace it

Apr 5, 2009.