Berlingo 2.0 l HDI starting issue- possibly connected to fuel cuttoff solenoid?

[nevajims]

Hi

Im new to this forum but have benefited from many of the posts over the years with my previous mark 1 berlingo -

my current car is a 2004 mark 2 berlingo multispce with a 2.0l HDI engine (rhy siemens)

got a really annoying problem basically occasionally it dosent start, but it turns over and we are pretty sure it is a problem of the fuel not getting through somehow, when it is working we can reproduce the precise symptoms by disconnecting the lead in the pic and it is connected to something that I think is the fuel cut off solenoid (marked in pic)- if so it looks like its non power up condition is closed, course that doesnt mean there is a fault in the solenoid- tracking down the problem is likely still going to be a pain, just wondering if we can bypass it to make it always open- dont think that would stop it working- what do you think? any ideas welcome

Ps
i have put an obd scanner in and there seems to be a fault coming up P1164 - which if cleared doesnt come back immediatly but does come back intermitantlly

[nevajims]

further to this post- im now not sure if this engine is the seimens or bosch version? had assumed it is seimens since didnt see an electric primer pump - but maybe this is not visable (at the tank?) so if anyone could tell me a simple way to know where its seimes or bosch I can check and update

[myglaren]

Put your VIN up and someone will ascertain exactly what is in your vehicle.

When you turn the ignition key but don't start the engine you may hear the in tank pump run for a few seconds.
You could also look for a primer under the bonnet, either a bulb or a button on the fuel filter.

[Hell Razor5543]

Hello, and to the Forum. Feel free to ask any questions; after all, that is the main reason the Forum is here; to help out those 'distressed French car owners' who have problems with their vehicles.

The best advise I can offer is you post the vehicle VIN here in this thread, so that a Moderator can then look up your vehicle on the Citroen system to see what she had when she rolled out of the factory. It is safe to do this, as the forum software will automatically obscure the VIN so only forum staff can read it.

[GiveMeABreak]

The crystal ball is out of crystals - VIN please.....

[nevajims]

Hi

thanks for the replies

the vin numer is VF7**************[VIN obfuscated, can be read by forum staff]

it does have a primer bulb which I have primed to see if it has any effect- there was originally some air bubbles in the tube between the fuel filter and the pump - but then I took out the filter housing out and refitted and dont seem to get the bubbles now but the problem still intermittantly persists.

jim

jim

[RichardW]

There's no shut off solenoid on the HDi - shut down of the engine is managed by the ECU stopping the injection. I suspect the fitting on the end of the pump is the pressure regulator - it won't start with that not powered, but it's not an on/off supply. VIN confirms Siemens injection. P1164 is rail pressure sensor coherence. This thread: viewtopic.php?t=30048 was about a similar problem, might be worth checking the connection to the rail pressure sensor (which I'm pretty sure is the red one in the photo above). Really you need some live data to see what it is doing when it won't start - i.e. is it seeing lots of pressure at standstill, or no pressure when running, or, or....

[GiveMeABreak]

P1164 usually relates to a problem with the lambda sensor at the exhaust to detect the oxygen levels and so inform the engine ECU, which can affect the air / fuel mixture. however, you don't have a lambda sensor on this vehicle and that fault code is not one that is coming up specifically for this vehicle.

However, on other vehicles with this fault, a possibility is a split in one of the air hoses is know to cause this error, so maybe worht a thorough examination of the air hoses - as even a small split can affect the air / fuel mixture (too lean / too rich).

This is the Air / Fuel component key parts:

(4) Speed Sensor
(6) Engine Speed Sensor
(7) Water Temp. Sensor
(10) Camshaft Position Sensor
(11) Accelerator Sensor (Pedal)
(19) Air Flow Meter

Unfortunately, vehicles this early had more limited diagnostic fault codes and often only provided basic EOBD codes for emissions related issues and even then these weren't that detailed.

[GiveMeABreak]

There's no shut off solenoid on the HDi - shut down of the engine is managed by the ECU stopping the injection. I suspect the fitting on the end of the pump is the pressure regulator - it won't start with that not powered, but it's not an on/off supply. VIN confirms Siemens injection. P1164 is rail pressure sensor coherence. This thread: viewtopic.php?t=30048 was about a similar problem, might be worth checking the connection to the rail pressure sensor (which I'm pretty sure is the red one in the photo above). Really you need some live data to see what it is doing when it won't start - i.e. is it seeing lots of pressure at standstill, or no pressure when running, or, or....

That thread was for P1166 Richard, not P1164 which is as I described above - but not directly coming up as a fault specific to this engine that I can see. But still worth checking the fuel rail sensor (14) on the diagram.

[nevajims]

ok great thanks- some stuff for me to try, ill get back when Ive tried these things- or with questions if i cant work out how to!

[nevajims]

When the car starts normally the fuel rail pressure rises steeply to the idling value (~3600 PSI)
When the starting problem occurs the fuel rail pressure does not go very high- around (300 - 500 psi)
I have now found that if you wait some time (10-15 minutes) and try again it has started normally.

it only has this problem occasionally (maybe 1 in every 30 starts- but does not weem to be predictable and is not dependant on the engine geing warmed up or not.

If you unplug the fuel pressure regulator (on the end of the pressure pump) then the same thing happen as the intermittent fault (and the pressure readings are similar).
I have unplugged the pressure regulator and measured the resistance across the connectors and it is 2.8 ohms - which according to the info I have is correct.

The end of the pressure pump has two pipes coming off it (see figure)- one plastic one which goes back to the tank and the other metal that goes to the fuel rail- I guess the regulator controls how much fuel goes down these two paths and Im guessing that when it is unplugged it allows the fuel to leak back to the tank so the pressure cant go to the required value?

When the car is running at idle - the fuel rail pressure sensor measure ~3600psi- if it is unplugged at this point the reading jumps up to 25000 PSI- so Im guessing that this gives a variable resitance proportional to pressure and the open circuit value is equivalent 25000psi.

To me it seems it is either a problem that the pressure regulator is occasionally not being activated (either ECU not sending signal or wires have a bad connection somewhere) or the mechanical device itself sometimes doesn't work

Doing a bit of a search round it seems like there is a fine mesh on the fuel pressure regulator which occasionally gets blocked and causes problems- although I don't know this would be intermittent

it would be nice to be able to measure the voltages going to the pressure regulator to try and narrow down the issue- some documentation talks about a break out box for ecu multi plug harness - is this a thing that can be bought- or something can be made ?

any suggestions on the next course of action would be welcome

there are a couple of explanatory figures attached

Jim