Not been on here for a few years life been getting in the way. Have a  174 09 plate and have a question. Just changed the tandem pump as it appeared to be leaking and finding it hard to prime the fuel system. The filter is a 2 pipe so I disconnected the return pipe at the elbow fitting near the filter and put a container underneath, the idea was to prime the system using cycling the ignition on and off. After 10 or so goes I thought I would check the container see if any fuel was coming out of the elbo but found a pool of diesel under the van....this had been squirting out of the brown pipe that goes to the tank and should be the return. Am I missing the trick or has the lift pump failed as well. What's odd is disconnecting the black tube (flo) at the filter also gives a flow of fuel when priming weird eh!

Any thoughts anybody.

Pete

The fuel from the low pressure pump in the tank comes up to the fuel filter, through the filter and then on to the tandem pump.  The pressure gets stepped up by the tandem pump then it arrives at the PD injectors and the real pressure increase happens as the camshaft squashes the injectors to inject the fuel as timed by the ECU.  The injection pressures are mind boggling!  The fuel is hot by now and goes back to the fuel filter (passing by a fuel temperature sensor) then through a fuel cooler radiator (easily visible under the floor) and then on back to tank.  

Yep it is different to older vans only two connections on the fuel filter.

 The return pipe is routed up near the filter then connected to the hard pipe 'brown' return line to cooler then tank. My understanding is the return goes into the lift pump lid and is  just a short pipe dropping fuel back in the tank. 

I just can't understand when priming it sends fuel up the flow and return when both pipes are disconnected in the engine bay....

Also there are less relays under the battery tray than my previous vans so obvious made a few changes here and there.

   

It does sound like they have swapped the the route of the return flow pipe on late vans.  I can see the advantage of returning the hot fuel via the filter to keep it from waxing in very cold temps but perhaps it's not deemed necessary any more for some reason.  

Anyways I wonder if the garage replaced the fuel sender at some point and got the  flow and return mixed up and he's had problems ever since.

I can't help much with the flow and return because I haven't seen the two-pipe version but I would find and check the flow from the pump and see what it does.  From your description it sounds like the tank pump is pumping fuel through both flow the and return pipes which must be wrong.

Edit- The data from the fuel temp senor is found in VCDS at group 007 in the first field.  It should be a  fairly close match to the coolant temp, intake air or ambient temp with a stone cold engine.  After that it should climb to a maximum of around 90 degrees C.  A poor fuel temp sensor can affect starting and running but a quick VCDS check live from cold could soon eliminate it as a culprit for any problems rather than just chucking in parts since it's not a very common fault.  

Fuel temp rising slowly always about 10 degrees lower than coolant temp.

Lumpy running on tickover smoothed out with higher revs.

At tickover

Inj 1 -2.31

Inj 2 -0.75

Inj 3 -0.38

Inj 4 -1.29

Inj 5 +plus 2.99

Is it likely I need a new injector loom?

Still no fault codes.....

If you're sure that your fault is definitely temperature related I would investigate all temp groups from cold as the engine warms up.  If 062 is available, have a look there.  If it is, you could log the results from cold and see if anything unusual is happening when your fault occurs.  (VCDS lite might not offer this though).

Even if VDCS lite doesn't offer the logging option you can still just watch each sensor from cold and see if the numbers look consistent and sensible. 

 Edit- Crossed post..

Where are you seeing those figures?  Group 13/14 I presume?  If so, the figure for inj 5 does look a bit high.  There is nothing to worry about with a few small plus figures on the 2.5 's but a set of minus figures are more common for a healthy system at idle with no faults but I wouldn't replace anything (unless it's very cheap/easy) on that basis.  

If it helps, here are my my figures from group 13 (and 14 for cyl 5) from a while back (2.5 AXE ) at idle with a not quite fully warm engine.

Inj 1 -071

Inj 2 -054

Inj 3 -079

Inj 4 -009

inj 5 -016

I think I would start with a new fuel filter primed with neat injector cleaner if you haven't tried that already.  Otherwise maybe get injector 5 cleaned and tested by a diesel specialist.  I haven't personally seen the injector loom fault but most that I have heard about cause clear misfires.  Your call though!     

1  -0.71

2 +0.33

3 +0.42

4  -0.49

5 +0.42

I remember mine runs for a second or so and then switches off once primed.  It's possible that it restarts once the engine is going but I don't know for certain.  

I take it your fuel is a good normal clean colour and not grey by being contaminated with engine oil?  Also that the engine oil doesn't smell of diesel and is not high on the stick.

I guess I'm just going to have to swap it out..

That part is very odd and is probably enough reason to take the pump out and test it at least.  It is a tank out job though.  

Will update with results.

The 09 sportline doesn't appear to have a fuel cooler unless it's moved somewhere else it's def not in the usual place. So now have to source a decent lift pump as not fitting the GSF one it's going back,

Same as before stuttering then cuts out and takes loads of cranking to start again. Always happens on a 4 ish mile plus journey when engine is up to normal operating temp.

You could see if parking facing downhill improves the starting.  What this proves is that it is a fuel problem rather than an electrical problem.  Downhill parking can improve starting caused by a faulty lift pump for instance simply because it improves the fuel flow.     

Any recommendations in ferndown dorset area for capable mechanic....

Cheers

When I heard the popping noise from the top end I immediately thought camshaft but its a very irregular popping so I'm thinking injector  Had fault codes come up. Cyl 5 misfire, maf sensor, glow plug and some code uil. ..can't remember  now. Put a new maf in and all I get now is Cyl 5 misfire and that's after a 10 mile run and she starts to run a bit rough. Am I right in saying if it was an injector fault she would run rough from cold start and nothe when she gets hot?  Otherwise I'm thinking injector loom replacement...

Re the injector- I think it depends on what is wrong.  But the few I have seen misfire hot or cold.

I took the van for mot and the mechanic there said it sounds like an injector chuffing. So could be the loom or injector on cyl 5.

I plan to strip the front end off next week and have a look. 

I want to change the loom but I'm struggling to even disconnect the injectors. Can anyone just go through disconnecting the loom and how to Unplug and remove without taking the bearing cap off.

Thanks

Pete