Fuel system Pressure

[Maicoman]

2009 Jetta 225k miles
This started as turbo actuator replacement. Removed valve cover to access the part. Crack, no start after priming as is normal procedure. No codes ran fine before removing the valve cover.
Changed fuel filter, no aluminum specks , some what dirtier than normal. I change at the recommended intervals. Checked fuel tank pump and intermediate pump, much crud replaced both.
Checked and cleaned HPP filter n290, fuel pressure regulator, hard lines and rail. Found what appeared to be fine rust throughout. Also attempted to clean and seat check valve in HHP. Seemed OK while blowing air through it. Cam and bucket were fine. Replaced pressure retention valve and orings. In regard to the fuel metering valve, I bench tested it with 12volts and while priming the system.

My question is why do I have over 100 lbs pressure going into the High Pressure Pump and only have 5 lbs out measured at the hard line to the rail while priming the system.
At what point do the electric pumps come on during start up?

 

[oilhammer]

Hmmmmm.... well, aside from me scratching my head about removing the valve cover for the VNT actuator, did you clean the cylinders out after the injectors were removed? Does the engine crank normally? The rail pressure sensor value should ramp up very quickly during cranking, I forget what the minimum is, but when there is an issue it usually stumbles out and stays pretty low.

 

[Maicoman]

With big arthritic hands I found it easier to go the valve cover route.
I did clean the carbon after removing the injectors and reinstalled with new crush washers and orings. Although on the first go round I installed the injector incorrectly, I had the brackets upside down. Would that damage anything?
Engine cranks good new battery. At one point after priming and cranking for what I thought was too long the motor started to stumble and then just stopped.
I only checked pressures during priming . Sounds like I should look at VCDS while cranking?
Thanks Hammer