Still reading 0 psi to the rail.

Replaced
3 rail mount gauges all said 0.
2 fuel pressure regs one afpr one new oem
New fuel filter
Tried stock pump reads 3-5psi
Tried new unused 255 walbro 0psi
Yet both pumps prime fuel to the rail (I disconnected the feed line and saw fuel coming out)

What's the deal!?

Would a burnt opti send a signal to the PCM to stop fuel pressure from building?

 

I have a new 255 coming thus Saturday

 

Are the fuel pressure gauges the "test" type that have a pin that depresses the core of the Schrader valve, or are they the permanent type that require that you remove the Schrader core before installing them?

 

All 3 we perm, the schrader is removed