Hi
can anyone help with the location of the fuel pump relay, need to have pump disconnected so i can run compression test

The relay (R103) is in the passenger side fuse box but I don't know if it is soldered to the board or has a socket, either way if you remove FS22 (20 amp) this will isolate the fuel pump.

thankyou

You can't "isolate" the (lift) pump as it's pure mechanical (not electric) and it's in the same body with the high pressure pump...
That electric pump is for equalizing the two halves of the fuel tank and not for sending fuel to the engine...
And neither disconnect the fuel line is not recommended as you should NOT let the high fuel pump and injectors starve as they lube themselves with the fuel.
For a compression test you should disconnect the engine ECU so that no fuel is injected (no injector energizing) and all the fuel is sent back to the tank via pressure control valve (which will be open in idle/no power state) and return line. So the fuel will circulate alright, but will not reach the cylinders' interior.
And, of course, to manually energize the starter motor as the starting system will not function with the engine ECU disconnected...

Would it be enough to disconnect injector connectors for compression test? Injectors not energized will not open starting system would work as always

alex_pescaru are you sure that the fuel pump sitting in the tank does not deliver the fuel to the fuelfilter and then from there the lift pump take over??

I have a TD4, which is cranking about not starting, no fuel going into the cylinder but there is fuel in the common rail. The injectors are not getting a 12v supply either.

Do you know what is causing this problem? I have checked all fuses and relays except the fuel pump relay, which it seems is soldiered to the the Central junction box thingy.

The tank pump doesn't pump fuel to the filter. All it does is pump fuel from one side of the tank to the other.

The injectors don't run on 12 Volts, but upwards of 120 Volts, and shouldn't be unplugged with the engine running.

How do you know there's sufficient pressure in the rail during cranking? Have you run diagnostic live data on the ECU? Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.

I don't have access to the ECU data, and the Land Rover workshop is far away. I am just checking things one by one. I have bled the high pressure pipes, there is fuel but i am not sure if there is enough pressure. One thing i am sure of is that the injectors are not firing because it sounds very lean when I crank it.

Last edited by Svensk on 1st Jan 2021 6:07 pm. Edited 1 time in total

From the workshop manual.
Published: 11-May-2011
Fuel Charging and Controls - TD4 2.2L Diesel - Fuel Charging and Controls
Description and Operation
COMPONENT LOCATION

Item
Part Number
Descriptionp
1
-
Common fuel rail
2
-
High pressure pipe – fuel rail to injector (4 off)
3
-
High pressure pipe – pump to fuel rail
4
-
Pipe – fuel rail pressure relief
5
-
Fuel rail pressure control valve
6
-
Hose - high pressure pump leak off
7
-
High pressure fuel pump
8
-
Low pressure hose – fuel filter to pump
9
-
Fuel filter assembly
10
-
Fuel temperature sensor
11
-
Pipe - injector leak off
12
-
Injector (4 off)
13
-
Fuel rail pressure sensor
OVERVIEW
The TD4 diesel engine fuel charging and control system provides precise and instantaneous fuel delivery to the combustion
chambers. This provides optimum performance, allowing the engine to be extremely responsive to driver demands for all driving conditions. The fuel system features a Bosch Generation 3 common rail injection system that is monitored and controlled by an engine control module (ECM), to precisely control the fueling strategy.
Fuel charging is achieved with a low and high-pressure fuel system. The low-pressure fuel system comprises;
a saddle type fuel tank
tank mounted fuel delivery module with integral transfer pump
fuel supply and return lines
filter and water separator assembly
a connecting hose between the fuel filter assembly and the fuel lift pump.
• NOTE: The fuel lift pump is integral with the high-pressure pump.
A return line and fuel leak off hoses from the high-pressure pump, injectors and common fuel rail form the remainder of the low-pressure fuel return circuit.
For additional information, refer to: Fuel Tank and Lines - 2.2L Duratorq-TDCi (DW) Diesel (310-01 Fuel Tank and Lines, Description and Operation).
The high-pressure fuel system comprises;
a high-pressure fuel pump
common fuel rail
4 piezo-injectors with high-pressure connection pipes a fuel pressure sensor.
The fuel charging and control system provides injection pressures of up to 1800 bar (26,106 psi). Finer atomization of the injected fuel is achieved with the 7 hole piezo injectors that are capable of near instantaneous response to the ECM commands, allowing up to 5 individual injections per stroke.
The high-pressure fuel pump is mounted at the rear of the cylinder head and is driven by the exhaust camshaft. A fuel lift pump is integral with the high-pressure pump and is therefore also driven when the exhaust camshaft rotates. The lift pump creates suction in the supply line to the fuel tank and draws the fuel from the tank. The fuel passes through the fuel filter and is then delivered at lift pump pressure to the high-pressure pump inlet port.
The advanced high-pressure fueling system enables pilot injections to be delivered ahead of the main charge of fuel. This produces a steady flame front and creates a progressive pressure rise in the cylinder similar to that achieved with petrol engines. This reduction in combustion lag between the injection of fuel and combustion occurring allows fuel to be injected while combustion is taking place, creating increased power and reducing created combustion noise, vibration and harshness (NVH) and emissions.
For models fitted with an exhaust system diesel particulate filter, the high-pressure fueling system also provides post combustion injection of fuel into the combustion chambers. When regeneration of the diesel particulate filter is requested, the ECM allows the fueling system to deliver fuel after the combustion stroke and into the commencement of the exhaust stroke. This post combustion injection process causes fuel to be burnt in the exhaust system and creates the high exhaust gas temperatures that are required to regenerate the diesel particulate filter.

Svensk wrote:

I don't have access to the ECU data, and the Land Rover workshop is far away. I am just checking things one by one. I have bled the high pressure pipes, there is fuel but i am not sure if there is enough pressure. One thing i am sure of is that the injectors are not firing because it sounds very lean when the crank it.

Is it possible to buy a cheap diagnostic tool för Freelander 2? Perhaps on Ebay?
I am aware of the risks, i had to bleed the fuel system because i had taken the engine apart.

The fuel system is self bleeding, you simply crank the engine. There's no need too release HP fuel unions, and its dangerous to do so.

Are you sure everything else is ok, if the engine has been apart? Hyundai Ioniq 5 Ultimate. The family car.
2009 Rimini Red SE TD4. Gone.
2006 Tonga Green i6 HSE. Gone.
Audi A5 convertible, my daily driver.
1972 Hillman Avenger GT, the project.

alex_pescaru wrote:

You can't "isolate" the (lift) pump as it's pure mechanical (not electric) and it's in the same body with the high pressure pump...
That electric pump is for equalizing the two halves of the fuel tank and not for sending fuel to the engine...
And neither disconnect the fuel line is not recommended as you should NOT let the high fuel pump and injectors starve as they lube themselves with the fuel.
For a compression test you should disconnect the engine ECU so that no fuel is injected (no injector energizing) and all the fuel is sent back to the tank via pressure control valve (which will be open in idle/no power state) and return line. So the fuel will circulate alright, but will not reach the cylinders' interior.
And, of course, to manually energize the starter motor as the starting system will not function with the engine ECU disconnected...

Fuel pump in the tank sucks fuel from both sides in a plastic "jar" ( venturi effect) from which the diesel lift pump deliver to high pressure pump.Just bought one to change the dead one .The level of diesel in the tank is calculateted by ecu. It is supposed that the level into the two halves of the tank are always equal. What if the pump dies, hapend to me on autobahn.ENGINE RUNS OUT OF FUEL but the diesel gauge shows you that you still have a quarter of the tank of fuel. Yelow MIL lights up. Engine cranks but doesn't run.You have no idea that the pump is kaput. The error code is P0087 Fuel Rail Too Low Bank1. You can check the pump fuse but you cannot check the relay that delivers 12v to the pump as is soldered on Central Junction Box, PCB. I know someone who once said, with Freel 2 you must always have a valid contract with a tow company.