L322 Range Rover M57 TD6 2004 3.0 diesel - fuel pump question

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Dr Veg

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Hi. I'm trying to diagnose a fuel delivery problem. Anyone know what the function is of each of the three hoses that connect to the in-tank fuel pump please ??? 1. Black 'quick-connect', 2. Blue 'quick-connect', 3. Black - clip.

See photo attached.
 

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Thanks backinblack for the super rapid reply!

So just to confirm, on my photo; the top (black) hose is the return, the middle (blue) is the delivery to the secondary pump and the bottom (black) is the FBH (fuel burning heater?).

When I turn the ignition I think I hear the pump running but there's no fuel emerging from the middle (delivery) line.
 
Should have asked what's the issue please?
The issue is healthy cranking but no start. I see air bubbles running through the transparent hose from the filter to the high pressure system. I get FUEL INJECT SYSTEM message on the dash. I've replaced both low pressure pumps but still the same issue. (No helpful error messages from my icarsoft diagnostics.)
 
So just to confirm, on my photo; the top (black) hose is the return, the middle (blue) is the delivery to the secondary pump and the bottom (black) is the FBH (fuel burning heater?).
Looking at the diagram yes. I'm looking to see if I have a picture of the secondary pump when I replaced it to see if the pipe is blue.
Have you replaced the fuel filter?
Have you disconnected the feed pipe and cranked it to see if fuel comes out, obviously into a container ?:)
Does the icarsoft give you fuel pressures?
The low pressure system pressure is approx. 1.5 bar to 5 bar and return end < 0.6 bar. The pressure in the high
pressure end is 200 bar to 1350 bar.
Does it start with easy start sprayed in the intake?
 
Looking at the diagram yes. I'm looking to see if I have a picture of the secondary pump when I replaced it to see if the pipe is blue.
Have you replaced the fuel filter?
Have you disconnected the feed pipe and cranked it to see if fuel comes out, obviously into a container ?:)
Does the icarsoft give you fuel pressures?
The low pressure system pressure is approx. 1.5 bar to 5 bar and return end < 0.6 bar. The pressure in the high
pressure end is 200 bar to 1350 bar.
Does it start with easy start sprayed in the intake?
The secondary pump intake fits onto a 5 way connector (9289A) in the attached diagram. So it's difficult to see if there's a blue hose there.
I haven't changed the filter because I changed it about 2000 miles ago when I did a service.
I did disconnect the feed pipe to the filter and fuel does flow out of it, but I think it's got air in it at this stage because I also hear the secondary pump buzzing as well as the fact that I see air in the transparent pipe that comes out of the filter.
The icarsoft doesn't give me pressures.
When I spray easystart over the air filter intake it does try to fire up.
 

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When I had the same symptoms but without the air bubbles it was a combination of the HP fuel pump and the pressure control valve. Although once it started with easy start it carried on running.
 
So I find that no fuel is coming out of the pump out hose (blue) though the pump is running. Somewhat unbelievably, the new in-tank fuel pump assembly I fitted is defective. I took it all out again and I saw that the fuel delivery pipe inside the unit is broken off of the electric pump itself, which explains why fuel was not being pumped out of the tank to the secondary pump. I'm expecting the supplier to replace it. Hopefully that should arrive in a few days!
 
Changed the in-tank pump. Checked it's working - delivers fuel out of the 'out' line when turned on. However, still no cigar...still same message on dash "FUEL INJECT SYSTEM" and I still hear the secondary pump (also new) buzzing as if it's pulling in air. Strange. The old pump was definitely broke so I'm a bit mystified as to why the new pump has not solved the problem. Not sure where to go from here.
 
Changed the in-tank pump. Checked it's working - delivers fuel out of the 'out' line when turned on. However, still no cigar...still same message on dash "FUEL INJECT SYSTEM" and I still hear the secondary pump (also new) buzzing as if it's pulling in air. Strange. The old pump was definitely broke so I'm a bit mystified as to why the new pump has not solved the problem. Not sure where to go from here.
Have you got fuel at the filter?
 
I'd suggest checking you have fuel coming out of the filter even though it's quite new.
Checking the fuel pressures.
Roughly where are you located as someone may live near you with diagnostics that can read fuel pressures.
 
I'd suggest checking you have fuel coming out of the filter even though it's quite new.
Checking the fuel pressures.
Roughly where are you located as someone may live near you with diagnostics that can read fuel pressures.
Yes I've got diesel coming out of the filter too. I sometimes see bubbles in the transparent pipe from the filter to the high pressure pump.

If the pressure sensor on the filter is dead - which I believe can trigger the FUEL INJECT SYSTEM message - would that disable the engine from starting up?

I live in France in the Perpignan area 😬.
 
Yes I've got diesel coming out of the filter too. I sometimes see bubbles in the transparent pipe from the filter to the high pressure pump.

If the pressure sensor on the filter is dead - which I believe can trigger the FUEL INJECT SYSTEM message - would that disable the engine from starting up?

I live in France in the Perpignan area 😬.
If the pressure sensor is dead, for sure the engine will not start. You should not see air bubbles in the fuel line. You really need proper diagnostics.
 
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