2002 LAND ROVER DISCOVERY fuel filter

ENGINE MANAGEMENT SYSTEM - TD5
18-1-50 REPAIRS
2.Disconnect multiplug from AAP sensor.
3.Release 2 clips and remove cover from air
filter.
4.Remove air filter element.
Refit
1.Clean air filter body and cover.
2.Fit new air filter element.
3.Position air cleaner cover and secure clips.
4.Position MAF sensor and secure clips.
5.Connect multiplug to AAP sensor.
Sensor - fuel temperature
$% 19.22.08
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Release fixings and remove battery cover.
3.Disconnect battery earth lead.
4.Disconnect multiplug from fuel temperature
sensor.
5. Thoroughly clean area around fuel
temperature sensor before removal.
6.Remove fuel temperature sensor and discard
sealing washer.
Refit
1.Clean fuel temperature sensor mating faces.
2.Fit new sealing washer and tighten fuel
temperature sensor to 13 Nm (10 lbf.ft) .
3.Connect multiplug to fuel temperature sensor.
4.Connect battery earth lead.
5.Fit battery cover and secure fixings.
6.Fit engine acoustic cover, and secure with
fixings.

ENGINE MANAGEMENT SYSTEM - TD5
REPAIRS 18-1-53
Element - fuel filter
$% 19.25.07
Remove
1.Release turnbuckles and remove battery cover.
2.Disconnect battery earth lead.
3.Raise rear of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
4.Clean area around fuel filter.
5.Disconnect multiplug from filter element.
6.Remove fuel filter element.
Refit
1.Clean fuel filter and mating face.
2.Fit new fuel filter element and connect
multiplug.
3.Remove stand(s) and lower vehicle.
4.Connect battery earth lead.
5.Fit battery cover and secure the fixings.
Cooler - fuel
$% 19.25.30
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Remove battery cover.
3.Disconnect battery earth lead.
4.Drain cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
5.Release 3 clips and disconnect 3 coolant hoses
from fuel cooler.
6.Release 2 fuel hoses from fuel cooler.
CAUTION: Always fit plugs to open
connections to prevent contamination.
7.Release vacuum pipe clip from fuel cooler.
8.Noting which bolts are removed from the upper
fixing holes, remove 4 bolts securing fuel cooler
to inlet manifold. Remove cooler.
Refit
1.Clean fuel hose connections.
2.Apply Loctite 242 to the two upper bolts.
3.Position fuel cooler to inlet manifold, fit bolts
and tighten the upper bolts to 18 Nm (13 lbf.ft)
and the lower bolts to 25 Nm (18 lbf.ft).
4.Connect fuel hoses to fuel cooler.
5.Connect coolant hoses to fuel cooler, secure
with clips.
6.Secure vacuum hose to fuel cooler.
7.Refill cooling system.

+ COOLING SYSTEM - Td5,
ADJUSTMENTS, Drain and refill.
8.Fit engine acoustic cover and secure with
fixings.
9.Connect battery earth lead.
10.Fit battery cover.

ENGINE MANAGEMENT SYSTEM - TD5
REPAIRS 18-1-59
Regulator - fuel pressure
$% 19.45.06
Remove
1.Release turnbuckles and remove battery cover
2.Disconnect battery earth lead.
3.Remove 3 bolts and remove engine acoustic
cover.
4.Remove 2 bolts and remove engine lifting eye.
5.Position cloth to absorb fuel spillage.
6.Release and disconnect hose from fuel cooler. 7.Release and disconnect fuel hose from
pressure regulator.
Always fit plugs to open connections to
prevent contamination.
8.Disconnect multiplug from fuel temperature
sensor.
9.Remove 3 bolts, remove pressure regulator
from cylinder head and collect gasket.
10.Remove and discard 'O' ring and fuel filter.

ENGINE MANAGEMENT SYSTEM - TD5
18-1-60 REPAIRS
11.Remove fuel temperature sensor and discard
sealing washer.
12.Remove fuel hose and fuel pipe and discard 'O'
rings.
Refit
1.Clean fuel pressure regulator and mating face.
2.Clean fuel pipe unions.
3.Using new 'O' rings, fit fuel pipe and fuel hose
to pressure regulator and tighten unions to 25
Nm (18 lbf.ft).
4.Using new sealing washer, fit fuel temperature
sensor and tighten to 14 Nm (10 lbf.ft).
5.Fit new fuel filter and 'O' ring.
6.Using a new gasket, position pressure
regulator and tighten bolts to 25 Nm (18 lbf.ft).
7.Connect multiplug to fuel temperature sensor.
8.Connect fuel hoses to pressure regulator and
fuel cooler.
9.Fit engine lifting eye and tighten bolts to 25 Nm
(18 lbf.ft).
10.Fit engine acoustic cover and tighten bolts to 10
Nm (6 lbf.ft).
11.Connect battery earth lead.
12.Fit battery cover and secure fixings.
Glow plugs
$% 19.60.31
Remove
1.Remove 3 bolts and remove engine acoustic
cover.
2.Release turnbuckles and remove battery cover.
3.Disconnect battery earth lead.
4.Disconnect 4 glow plug leads.
5.Loosen and remove 4 glow plugs.
Refit
1.Thoroughly clean glow plugs and seating area
in cylinder head.
2.Apply a suitable anti-sieze compound to
threads of glow plugs.
3.Fit glow plugs and tighten to 16 Nm (12 lbf. ft).
4.Connect glow plug leads.
5.Fit engine acoustic cover and secure fixings.
6.Connect battery earth lead.
7.Fit battery cover and secure fixings.

ENGINE MANAGEMENT SYSTEM - V8
DESCRIPTION AND OPERATION 18-2-25
Throttle Position (TP) sensor (C0175)
The TP sensor is located on the throttle body assembly in the engine compartment. The ECM is able to determine the
position of the throttle plate and the rate of change of its angle. The ECM processes the signal received from the TP
sensor.
The TP sensor consists of a resistance track and a sliding contact connected to the throttle plate assembly. As the
throttle is opened and closed the sliding contact moves along the resistance track to change the output voltage of the
sensor. The ECM determines throttle plate position by processing this output voltage. The connection of the sensor
to the throttle plate assembly is via a shaft.
The ECM is able to determine the closed throttle position, this enables the TP sensor to be fitted without the need for
prior adjustment. The TP sensor signal has input into the ECM's fuelling strategy and also to determine closed throttle
position for idle speed control. The TP sensor also supplies the ECM with information to enable the overrun fuel cut
off strategy to be implemented. When the ECM receives closed throttle information from the TP sensor it closes the
injectors for the duration of the closed throttle time.
The TP sensor signal is also used by the Electronic Automatic Transmission (EAT) ECU to determine the correct point
for gear shifts and acceleration kickdown. The ECM also supplies the SLABS ECU with this TP sensor information as
a PWM signal.
Input/Output
The TP sensor has electrical input and output. Input is a 5 volt supply via pin 10 of connector C0636 of the ECM. The
signal output is via pin 24 of connector C0636 and is a varying voltage, less than 0.5V (closed throttle) and greater
than 4.5V (wide open throttle) depending on throttle plate position. The TP sensor earth is via pin 25 of connector
C0636 of the ECM, this acts as a screen to protect the integrity of the TP sensor signal.
The connector and sensor terminals are gold plated for corrosion and temperature resistance, care must be exercised
while probing the connector and sensor terminals.
If the TP sensor signal fails, the ECM uses a default value derived from engine load and speed.
The TP sensor can fail the following ways or supply incorrect signal:
lSensor open circuit.
lShort circuit to vehicle supply.
lShort circuit to vehicle earth.
lSignal out of parameters.
lBlocked air filter (load monitoring, ratio of the TP sensor to air flow).
lRestriction in air inlet (load monitoring, ratio of the TP sensor to air flow).
lVacuum leak

FUEL DELIVERY SYSTEM - TD5
DESCRIPTION AND OPERATION 19-1-1
FUEL DELIVERY SYST EM - Td5 DESCRIPTION AND OPERAT ION
Fuel delivery system component
location
A = Pre EU3 models
1HP stage
2LP stage
3Filters
4Jet pump
5Fuel pump and fuel gauge sender assembly
6LP return connection
7LP feed connection
8HP feed connection9Air bleed connection
10Fuel filter
11Water sensor
12Fuel cooler
13Fuel pressure regulator (EU3 models)
14Electronic unit injectors
15Fuel pressure regulator (pre EU3 models)
16Electronic unit injectors

FUEL DELIVERY SYSTEM - TD5
DESCRIPTION AND OPERATION 19-1-3
Description
General
The fuel delivery system comprises a fuel tank, fuel pump, fuel pressure regulator, five injectors and a fuel filter. The
system is controlled by the Engine Control Module (ECM) which energises the fuel pump relay and controls the
operation and timing of each injector solenoid.
Unlike other Diesel engines, the Td5 engine has no injection pump. The diesel direct injection system receives fuel
at pressure from a two stage fuel pump located in the fuel tank. The system incorporates a fuel return to the fuel pump,
via a fuel cooler attached to the inlet manifold and a fuel filter. A fuel pressure regulator is located in a housing on the
rear of the cylinder head. The regulator maintains the fuel delivered to the injectors at a constant pressure and returns
excess fuel back to the fuel filter and pump via the fuel cooler.
A fuel filter is positioned on the chassis to the right of the fuel tank. The fuel feed and return to and from the engine
passes through the filter. The filter also incorporates a water sensor which illuminates a warning lamp in the
instrument pack.
A moulded fuel tank is located at the rear underside of the vehicle between the chassis longitudinals. The tank
provides the attachment for the fuel pump and fuel gauge sender unit which is located inside the tank.
Fuel tank and breather
The fuel tank and breather system is a major part of the fuel delivery system. The fuel tank and breathers are located
at the rear of the vehicle between the chassis longitudinals.
Fuel tank
The moulded fuel tank is made from High Molecular Weight (HMW) High Density Polyethylene (HDPE). The diesel
tank is manufactured using a proportion of recycled plastic.
The tank is retained in position by a metal cradle which is secured to the chassis with two nut plates and bolts at the
rear and a stud plate and two nuts at the front. A strap above the tank is bolted to the chassis and restrains the tank
from moving upwards. The fuel tank has useable capacity of approximately 95 litres (25 US Gallons).
An aperture in the top surface of the tank allows for the fitment of the fuel pump and fuel gauge sender unit which is
retained with a locking ring.
A reflective metallic covering is attached to the tank with two scrivets to shield the tank from heat generated by the
exhaust system.
The fuel filler is located in the right hand rear quarter panel, behind an access flap. The flap is opened electrically
using a switch on the fascia which operates a release solenoid.
The filler is closed by a threaded plastic cap which screws into the filler neck. The cap has a ratchet mechanism to
prevent overtightening and seals against the filler neck to prevent the escape of fuel vapour. The filler cap has a valve
which relieves fuel pressure to atmosphere at approximately 0.12 to 0.13 bar (1.8 to 2.0 lbf.in
2) and opens in the
opposite direction at approximately 0.04 bar (0.7 lbf.in2) vacuum.
A moulded filler tube, made from HMW HDPE, connects the filler to the tank via a flexible hose. The filler tube is
connected at its top end behind the filler flap.

FUEL DELIVERY SYSTEM - TD5
19-1-4 DESCRIPTION AND OPERATION
Fuel tank breather system
The filler tube incorporates a tank vent which allows air and fuel vapour displaced from the tank when filling to vent to
atmosphere via the filler neck.
A breather spout within the tank controls the tank 'full' height. When fuel covers the spout it prevents fuel vapour and
air from escaping from the tank. This causes the fuel to 'back-up' in the filler tube and shuts off the filler gun. The
position of the spout ensures that when the filler gun shuts off, a vapour space of approximately 10% of the tanks total
capacity remains. The vapour space ensures that the Roll Over Valve (ROV) is always above the fuel level and vapour
can escape and allow the tank to breathe.
The ROV is welded on the top surface of the tank. The ROV is connected by a tube to the filler tube, which in turn is
connected to the atmospheric vent pipe. The ROV allows fuel vapour to pass through it during normal vehicle
operation. In the event of the vehicle being overturned the valve shuts off, sealing the tank and preventing fuel from
spilling from the atmospheric vent pipe.
Fuel pump and fuel gauge sender
1Fuel burning heater feed pipe connection
2Air bleed connection (natural)
3HP feed connection (green)
4LP feed connection (blue)
5LP return connection (black)
6Pump feed pipe
7Spring 2 off
8Fuel gauge sender unit9Swirl pot
10Gauze filter
11Fuel gauge sender float
12Electrical connections
13HP/LP two stage pump
14Pump LP return pipe
15Electrical connector