having a bit of grief with the girl , going uphill usually and randomly into limp mode and p0087-22 set in ecu.

usually will drive ok when code cleared. sometimes have to add diesel before clearing usually if there is about 30 miles rannge but gotten worse now.

will set this code even with a full tank. and now will not start by herself.

fuel lines are empty. i can bleed the system of air no problem with electric pump on the return pipe at the diesel filter . car will then start. if i turn off and on within a minute it will start back up. the longer i leave it the harder to start .after a few hours wont start. and i have to bleed the air again.
once its running its fine until i put a bit of throttle when driving.

i have narrowed it down to the following possibilities . what are your thoughts

1 change diesel filter to a lr one (its got some blue coloured 1 on it now.)
2 change the fuel pressure regulator on end of rail (see below for reasoning)
3 injectors suffering sever leak off
4 the fuel pump and senders in the tank , incase the delivery side is empty..... bad jets or delivery pot goosed (do this last as its biggest job).

as for number 2 above

here is some live data while driving , including the moment the error code is set, im tending to lean towards the needle becoming stuck and letting fuel leak off from the rail.
also as soon as i turn the engine off the rail is dropping to 0 psi (im unsure if it should do this or remain at a certain psi , any info would be greatly recieved).
the delivered psi is very eeratic up and down across the desired rail pressure here are the live data


1st spike , error code set



at idle with a little rev




also unsure where the check valve is (presuming in the hs pump) and what part of the fuel system it will prevent fuel running back (again any info greatly appreciated)

and finally , are the injectord high pressure leak off making a simple leak off test no good?

many thanks for any help,assistance or figures etc
kind regards
martin