I have a FP 4022-10...it is relatively new but will not generate enough pressure to actuate power cutoff, so the pump runs till I unplug it. I have verified that the line to the lake is clear (water backflows through pump to the intake (foot valve removed for this test) via another pump system at 7 to 8 gallons per minute) I get water flow but cannot get pump to build above 30 lbs, no leaks external to pump. how do I remove pump housing from electric motor? 4 bolts are removed but housing will not come off.

No cutoff switch that I know of.
Only Ford products use an inertia switch and that cuts power to the pump in case of a wreck.
Is the pump running when you turn the key on ?

Fuel filter may be clogged!
It's attached to the fuel pump.

if it did not have an electric fuel before then the installation of an electric pump is a relatively easy process. If you have an electric pump already fitted but it has failed then remove it and install the new pump in its place. Take care to check all wires, fuses and relays and any pressure sensors for correct operation. Remove and blank of the opening for any mechanical pump on the engine
For new installation select an easily accessible place under the vehicle that can be protected from flying rocks and road debris. Run a power wire (red colour) from the run side of the ignition switch to the relay ( to be fitted ) near the battery or in the engine bay. Run this wire through an inline fuse close to the ignition switch to protect the circuit. attach to a coil actuation terminal of the relay.( look at the base of the relay for terminal identification. Run a black wire from the other side of the coil actuation pin on the relay to earth. Normally the same bolt that mounts the relay. Run a red wire capable of carrying 20 amps directly from the battery terminal through an inline fuse ( close to the terminal) to a power pin on the relay. Run another red wire from the outlet power pin on the relay to the electric pump. . Run an earth wire from the pump to earth.
This is a basic electric circuit for the installation of the pump. If there is a requirement for a pressure regulator or pressure sensor to control the pressure or pump operation , that control wire will be connected in series into the wire from the ignition switch so that when the pressure is reached then it breaks the circuit to the relay from the ign. switch and the pump will stop operation until the circuit is again completed. When the ignition switch is off there will be no power for the pump

I would say it is fuel related, Either the lift pump not supplying enough fuel to the high pressure fuel pump or maybe the high pressure pump itself. But really there is not enough info here to make a good diagnoses. It could also be a perished turbo.

The refrigerant may be low or empty due to a leak. If not here are a few ideas you can try. If there isn't any refrigerant in the system, you WILL damage the compressor if you bypass any of the safety switches to test. The low pressure cutoff switch or high pressure cutoff switch may be bad. Try removing the low pressure switch electrical connector and jumping across it with a paper clip.

Check the oil pressure cutoff switch. If oil pressure is not sensed or for some reason the switch doesn't activate the engine is killed when you return the keyswitch to the run position.

Acura doesn't use a fuel pump cutoff switch.

You suspect this unit as being a two stage because of the unusually high cut off pressure. It is a single stage and the motor really has a difficult task and is being pushed to the limits. to reach this pressure. We usually reset the pressure to lower setting ~~ say around 140. Your pump probably has a leaking intank check valve (brass fitting at tank) or leaking valve plate in pump. Simple tests : with pressure in tank unplug compressor from outlet and listens for air leak around pressure switch. As you unplug the running compressor from outlet you should hear air leaking from pressure switch for just a moment as air is let out of airline from pump to tank. If air leaks out till zero pressure then change the valve. If tank holds pressure then valve probably ok. Next test, with no air in tank and air filter removed, plug in compressor and feel intake port for strong suction. If the valve plate is bad, suction will decrease as pressure neers the 120 mark till the point of feeling that air is actually blowing out of intake. With good valve plate there will be strong suction untill unit reaches set pressure. If valve plate is bad also change the cylinder and piston ring. Good luck with your repair.

Depending where you live and how high your minerals run in the water. If it is old enough to change the liner it is probally old enough to get new socks for the fingers.

there is a unit called a fuel pressure regulator that controls the FP operation
when the pressure is low it starts the pump and when the pressure reaches a preset value it switches the pump off
AH-- I hear you say the pump works when it has direct 12 volts
true but the engine runs on quick start but not from fuel supplied
that is probably because the pressure switch is not working and there is no pressure for the injectors
IF you were to bring it to my shop , that is where I would start looking for the problem and I would recommend changing that pressure switch