Fuel rail/system pressure too low

[piki]

C3 Picasso 2012 , 1.6 hdi diesel .
got this got code (Fuel rail/system pressure too low) 2 month ago .
tried to replace the fuel filter and clearing the code , it worked for 2 month now the fault and the limp mode are back.
i have read online it code be the Fuel rail pressure switch.
any thoughts?

[piki]

so im putting my fuel from a tank we have in the yard, and i opened the fuel pump in the tank , and i found some leaves in the pump , and it went through the strainer in it.
i have tried to change filter again , still throw the fould code (p0800 i think) -fuel rail pressure low.
where it could be blocked before the filter? i have seen the line is going straight to the filter?
could a dirt pass the filter to the high pressure pump? or to the injectors?

[piki]

also i cheked with the diagbox , and the rail preesure value and the pressure were good , after a while of driving , it will turn on the check engine , and a day later it will turn off,
and so on.

[GiveMeABreak]

This is going to be difficult to track down if you suspect contamination. I'd suggest you put some diesel diesel injection fuel system cleaner when you next fill the tank. Your other issue may be that if you are using diesel from you own storage tank that you may be introducing diesel sludge or other bacteria / contaminants from the tank into your vehicle. Don't allow your vehicle to run with the fuel tank too low - this is where any dirt and contaminants will be concentrated and will get picked up.

[piki]

never knew there is something like that . i will defiantly gonnsa try that,
will also try the 2th thing bout tank too low ,
ty marc

[GiveMeABreak]

Here's the fuel circuit diagram so you can see how everything comes together on this system It may help you with checks....

Click Image to Magnify

Key:
"A" Electrical links
"B" Low pressure fuel circuit
"C" High pressure fuel circuit
"D" Heated low pressure fuel circuit

Reference	Designation	Electrical diagram correspondence
(1)	Fuel high pressure common injection rail	-
(2)	Engine ECU	1320
(3)	Fuel cooler	-
(4)	Fuel tank	-
(5)	Fuel filter	-
(6)	Diesel injector (1) ; (2) ; (3) ; (4)	(1331, 1332, 1333, 1334)
(7)	high pressure fuel pump	1208
(8)	Fuel flow regulator	1208
"a"	Fuel high pressure sensor	1321
"b"	Integral diesel fuel heater	1276
"c" (*)	Water in fuel sensor	4050
"d"	Manual fuel primer pump	-

[piki]

TYSM

[MGmike]

I'm assuming the error code is P0087.
Once you've cleaned the fuel system and eliminated contamination, I would start with an injector leak down test (YouTube will help). A common cause of lower fuel pressure is from one or more injectors passing more fuel to the return than it/they should be.

[piki]

ok , ordered some diesel cleaner, will see if it works .
i whould assume its some dirt in the system , becouse if im not driving hard , it wont come on for days.
only going uphill as well ... so i dont think its from the injectores once i know there was contamination in the tank.

[Rp0thejester]

Do you have a DPF fitted??

[piki]

I do have PDF

[Rp0thejester]

Ah, that might be the issue

[GiveMeABreak]

You'd get a warning for the DPF separately if there was an issue - so still the fuel system in my opinion - also given the hill issue where it could be sucking in the dregs from the bottom of the tank.

[piki]

OK
so just finished 2 cans of diesel cleaner, (2 tanks).
changed the fuel filter again, cleared the ecu , still the fualt coming back.
i was thinking maby what mike suggested, that the dirt got into the injectors , and clogged it up , causing too much fuel to go back the return line, make any sense?
i think my next move is to get the leak down test kit, and also i thought to use liqui moly purge straight into the fuel filter to clean it , any recommendation on this product?

[piki]

So i tried to use the test kit for return line , none of the adaptor fits the injector return hole.
do i need spaciel adaptor to do the test?