(SOLVED) Weird fuel pressure symptoms

[dndj]

Oh it Showed max pressure with it unplugged but my diagnosis method ended up tricking me.
The pressure regulator was stuck at 9000psi.
With the pressure sensor disconnected my tech2 gave me the illusion that I was controlling the “pressure” but it was controlling something else that was changing the idle quality when modifying fuel rail pressure.
(If anyone has any insight on what was being controlled with both the fpr frps unplugged that would be awesome)

Just chiming in to answer this question. Since you were modifying the desired fuel rail pressure with your Tech2, the change in idle sound you observed was the ECM selecting a different cell of the main injection pulse table and injector PW. For a given quantity of fuel, say 10mm3 while idling, the main injection pulse table is mapped across the full range of fuel pressures resulting in an appropriate injector pulse width.