low oil pressure LAND ROVER DISCOVERY 2002 Workshop Manual

CONTENTS
CONTENTS 7
Operation ........................................................................................................................................ 18-1-38
ADJUSTMENTS
Glow plug ....................................................................................................................................... 18-1-45
REPAIRS
Engine control module (ECM) ........................................................................................................ 18-1-47
Sensor - engine coolant temperature (ECT) ................................................................................. 18-1-47
Sensor - crankshaft (CKP) .............................................................................................................. 18-1-48
Air filter assembly ........................................................................................................................... 18-1-48
Element - air filter ............................................................................................................................ 18-1-49
Sensor - fuel temperature .............................................................................................................. 18-1-50
Sensor - mass air flow (MAF) ....................................................................................................... 18-1-51
Sensor - combined MAP and IAT ................................................................................................. 18-1-51
Sensor - ambient air pressure (AAP) ............................................................................................ 18-1-52
Element - fuel filter ........................................................................................................................ 18-1-53
Cooler - fuel .................................................................................................................................. 18-1-53
Sensor - Throttle position (TP) ........................................................................................................ 18-1-54
Turbocharger ................................................................................................................................ 18-1-55
Intercooler ..................................................................................................................................... 18-1-56
Valve - solenoid boost control ........................................................................................................ 18-1-58
Regulator - fuel pressure .............................................................................................................. 18-1-59
Glow plugs ...................................................................................................................................... 18-1-60
Injectors .......................................................................................................................................... 18-1-61
Switch - cruise control (on/off) ........................................................................................................ 18-1-62
Switch - cruise control (set/resume) ................................................................................................ 18-1-63
Switch - clutch ................................................................................................................................. 18-1-63
ENGINE MANAGEMENT SYSTEM - V8 .................................................. 18-2-1
DESCRIPTION AND OPERATION
Engine management component location - Passenger compartment ............................................ 18-2-2
Engine management component location - Engine compartment .................................................. 18-2-3
Engine management block diagram ............................................................................................... 18-2-4
Description - engine management .................................................................................................. 18-2-6
Operation - engine management .................................................................................................... 18-2-43
DESCRIPTION AND OPERATION
Cruise control component layout .................................................................................................... 18-2-55
Cruise control block diagram .......................................................................................................... 18-2-56
Description - cruise control ............................................................................................................. 18-2-57
Operation - cruise control................................................................................................................ 18-2-66
ADJUSTMENTS
Cable - throttle ............................................................................................................................. 18-2-69
Cable - cruise control .................................................................................................................... 18-2-69
REPAIRS
Spark plugs .................................................................................................................................. 18-2-71
Coil - ignition ................................................................................................................................. 18-2-71
Engine control module (ECM) ......................................................................................................... 18-2-72
Sensor - engine coolant temperature (ECT) ................................................................................ 18-2-73
Sensor - crankshaft position (CKP) ............................................................................................... 18-2-74
Sensor - radiator temperature ....................................................................................................... 18-2-75
Sensor - camshaft position (CMP) ................................................................................................. 18-2-76

GENERAL INFORMATION
03-25
lComponents must not remain uncapped for
longer than 15 minutes. In the event of a delay,
the caps must be fitted.
lWhen disconnecting, immediately cap all air
conditioning pipes to prevent ingress of dirt and
moisture into the system.
lThe receiver/drier contains desiccant which
absorbs moisture. It must be positively sealed at
all times. A receiver/drier that has been left
uncapped must not be used, fit a new unit.
lThe receiver/drier should be the last component
connected to the system to ensure optimum
dehydration and maximum moisture protection
of the system.
lWhenever the refrigerant system is opened, the
receiver/drier must be renewed immediately
before evacuating and recharging the system.
lUse alcohol and a clean lint-free cloth to clean
dirty connections.
lEnsure that all new parts fitted are marked for
use with R134a.
When a major repair has been completed, a leak test
should be conducted; refer to the Air Conditioning
section of this manual for the correct procedure.
Refrigerant oil
Refrigerant oil easily absorbs water and must not
be stored for long periods. Do not pour unused
refrigerant oil back into the container. Always
use an approved refrigerant oil.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Lubrication.
When replacing components in the A/C system,
drain the refrigerant oil from the component being
replaced into a graduated container. On assembly,
add the quantity of refrigerant oil drained to the new
component.
Compressor
A new compressor is sealed and pressurised with
Nitrogen gas. When fitting a new compressor, slowly
release the sealing cap; gas pressure should be
heard to vent as the seal is broken.
CAUTION: A new compressor should always be
sealed and could be pressurised with nitrogen
gas. To avoid possible oil loss, release the
sealing cap(s) slowly. Do not remove the cap(s)
until immediately prior to connecting the air
conditioning pipes to the compressor.Rapid refrigerant discharge
If the air conditioning system is involved in accident
damage and the system is punctured, the refrigerant
will discharge rapidly. The rapid discharge of
refrigerant will also result in the loss of most of the oil
from the system. The compressor must be removed
and all the remaining oil in the compressor drained
and refilled as instructed in the air conditioning
section of this manual.
Precautions for refrigerant recovery, recycling
and recharging
When the air conditioning system is recharged, any
existing refrigerant is first recovered from the system
and recycled. The system is then charged with the
required weight of refrigerant and volume of
refrigerant oil.
WARNING: Refrigerant must always be recycled
before re-use to ensure that the purity of the
refrigerant is high enough for safe use in the air
conditioning system.
Recycling should always be carried out with
equipment which is design certified by
Underwriter Laboratory Inc. for compliance with
SAE J1991. Other equipment may not recycle
refrigerant to the required level of purity.
A R134a Refrigerant Recovery Recycling
Recharging Station must not be used with any
other type of refrigerant.
Refrigerant R134a from domestic and
commercial sources must not be used in motor
vehicle air conditioning systems.
CAUTION: The system must be evacuated
immediately before recharging commences.
Delay between evacuation and recharging is not
permitted.

GENERAL INFORMATION
03-26
Air Conditioning Compressor
Replacement
A new compressor is supplied filled with a full charge
(X cm3) of refrigerant oil.

+ CAPACITIES, FLUIDS AND
LUBRICANTS, Capacities.A calculated quantity of
oil must be drained from the new compressor before
fitting. To calculate the quantity of oil to be drained:
1Remove the drain plug from the old
compressor.
2Invert the compressor and gravity drain the oil
into a calibrated measuring cylinder. Rotate the
compressor clutch to ensure the compressor is
completely drained.
3Note the quantity of oil drained (Y cm
3).
4Calculate the quantity of oil to be drained from
the new compressor using the following
formula:
X cm
3 — (Y cm3 + 20 cm3) = Q cm3
5Remove the drain plug from the new
compressor and drain Q cm3 of oil. Fit and
tighten the compressor drain plug.
Body Repairs
General
Body shells are of welded construction and bolted to
a chassis frame. Front and rear sections of the shell
are designed as 'energy absorbing' zones. This
means they are designed to deform progressively
when subjected to impact in order to minimise the
likelihood of injury to vehicle occupants.
It is essential that design dimensions and strength
are restored in accident rectification. It is important
that neither structural weakness nor excessive local
stiffness are introduced into the vehicle during body
repair.
Repairs usually involve a combination of operations
ranging from straightening procedures to renewal of
individual panels or panel assemblies. The repairer
will determine the repair method and this decision will
take into account a balance of economics between
labour and material costs and the availability of repair
facilities in both equipment and skills. It may also
involve considerations of the vehicles' downtime,
replacement vehicle availability and repair turn-
around time.
It is expected that a repairer will select the best and
most economic repair method possible, making use
of the facilities available. The instructions given are
intended to assist a skilled body repairer by
expanding approved procedures for panel
replacement. The objective is to restore the vehicle
to a safe running condition by carrying out a repair
which is as close as is feasible to original standard.
The results should not advertise to the experienced
eye that the vehicle has been damaged, although the
repair might not be identical in all respects to the
original factory build. Commercial bodyshop repair
facilities cannot always duplicate methods of
construction used during production.
Operations covered in this Manual do not include
reference to testing the vehicle after repair. It is
essential that work is inspected and suspension
geometry checked after completion. Where
necessary a road test of the vehicle should be carried
out, particularly where safety-related items are
concerned.
Where major units have been disconnected or
removed it is necessary to ensure that fluid levels are
checked and topped up where necessary. It is also
necessary to ensure that the repaired vehicle is in a
roadworthy condition in respect of tyre pressures,
lights, washer fluid etc.

GENERAL DATA
04-2
Lubrication
Type Wet sump, pressure fed
Pump type Eccentric rotor, crankshaft driven integral with stiffener plate.
Filter type:

Primary Centrifuge filter

Secondary Disposable canister with full flow by-pass
Pressure at idle (Cold) 3.0 bar (43.5 lbf.in
2)
Pressure at 3500 rev/min (Hot) 1.5-3.0 bar (21.75-43.5 lbf.in
2)
Relief valve opening pressure 4.0 bar (58 lbf.in
2)
Low oil pressure switch opening pressure 0.2-0.6 bar (3.0-8.8 lbf.in
2)
Crankshaft
Main journal diameter 61.9875-62.0125 mm (2.4404-2.4414 in)
Crankpin journal diameter 53.99-54.01 mm (2.125-2.131 in)
End float 0.020 - 0.250 mm (0.0008 - 0.0098 in)

Main bearings
Quantity 6 (5 main, 1 thrust)

Pistons
Type Graphite compound skirt with combustion chamber in crown
Clearance in cylinder bore.
Measured at bottom of skirt, 90° to gudgeon pin0.172-0.206 mm (0.007-0.008 in)
Diameter
(Measured at right angles to gudgeon pin and 40.0
mm (1.5 in) from bottom of skirt)84.270-85.254 mm (3.321-3.361 in)
Gudgeon pins Fully floating, offset towards piston thrust side
Piston rings
Type: 2 compression, 1 oil control

Upper compression ring Barrel edge, chrome plated

Lower compression ring Taper faced

Oil control ring Bevelled ring with spring
New ring to groove clearance:

Upper compression Not measured

Lower compression 0.050-0.082 mm (0.002-0.003 in)

Oil control 0.050-0.082 mm (0.002-0.003 in)
Piston ring fitted gap in cylinder bore:

Upper compression 0.30-0.45 mm (0.0118-0.0177 in)

Lower compression 0.40-0.60 mm (0.0157-0.0236 in)

Oil control 0.25-0.40 mm (0.0098-0.0157 in)

GENERAL DATA
04-5
Idle speed:

All loads off 660 ± 50 rev/min

Base idle speed Non-adjustable

Idle air control (IAC) valve position Checked via TestBook
CO at idle:

Catalyst vehicles 0.5 %

Non-catalyst vehicles 0.5 - 1.0 %
Valve timing
Inlet valves:

Opens 28° BTDC

Closes 77° ABDC
Exhaust valves:

Opens 66° BBDC

Closes 39° ATDC
Fuel grade:

High compression catalyst vehicles 95 RON minimum unleaded

Low compression catalyst vehicles 91 RON minimum unleaded

Non-catalyst vehicles 97 RON leaded
Lubrication
Type Wet sump, pressure fed
Pump type Crankshaft driven eccentric rotor
Oil filter Disposable canister with full flow by-pass
Pressure at idle - minimum 0.7 bar (10 lbf.in
2)
Pressure at 2000 rev/min (hot) 3.4 bar (50 lbf.in
2)
Relief valve opening pressure 3.4 bar (50 lbf.in
2)
Low oil pressure switch opening pressure 0.24-0.41 bar (3.5-6.0 lbf.in
2)
Crankshaft
Main journal diameter 63.487 - 63.500 mm (2.4995 - 2.520 in)
Crankpin journal diameter 55.500 - 55.513 mm (2.20 - 2.22 in)
End float 0.08 - 0.26 mm (0.003 - 0.010 in)
Maximum ovality 0.040 mm (0.002 in)
Main bearings
Quantity 5
Material Glacier Vandervell / AS 15
Diametrical clearance 0.015 - 0.016 mm (0.00059 - 0.00063 in)
Connecting Rods
Type Horizontally split big-end, plain small end
Distance between centres 155.120 - 155.220 mm (6.1071 - 6.1110 in)

GENERAL DATA
04-17
Air conditioning
Electrical - Td5
Electrical - V8
Type CFC free, sealed closed loop
Compressor:

Displacement 177.7 cm
3/rev (10.84 in3/rev)

Relief valve operating pressure 34.3 to 41.4 bar (497 to 600 lbf.in
2)

Refrigerant oil quantity 180ml (6.3 fl.oz)
Dual pressure switch operating pressures (nominal):

Low pressure switch Opens 2.0 bar (29.0 lbf.in
2), pressure decreasing

Low pressure switch Closes 2.3 bar (33.4 lbf.in
2), pressure increasing

High pressure switch Opens 32 bar (464 lbf.in
2), pressure increasing

High pressure switch Closes 26 bar (377 lbf.in
2), pressure decreasing
System 12 volt, negative earth
Battery:

Type Delco Freedom

Capacity 110 amp hour
Alternator:

Type Nippon Denso

Maximum output 120 amp
Starter motor:

Type Nippon Denso

Power 2 kW
System 12 volt, negative earth
Battery:

Type Delco Freedom

Capacity 72 amp hour
Alternator:

Type Bosch NC65/130

Maximum output 130 amp
Starter motor

Type Nippon Denso

Power 1.8 kW

TORQUE WRENCH SETTINGS
06-5
Emission control - Td5
Emission control - V8
Engine management system - Td5
TORQUE DESCRIPTION METRIC IMPERIAL
EGR valve pipe Allen screws 10 Nm (7 lbf.ft)
EGR valve to inlet manifold bolts 10 Nm (7 lbf.ft)
EGR intake pipe clip to cylinder head bolts - if fitted 25 Nm (18 lbf.ft)
EGR cooler to cylinder head nut and bolts - if fitted 25 Nm (18 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
HO
2S Sensors45 Nm (33 lbf.ft)
SAI air manifold union nuts 25 Nm (18 lbf.ft)
Rubber mountings to SAI pump bracket 10 Nm (7 lbf.ft)
SAI control valve to manifold bolts 10 Nm (7 lbf.ft)
SAI pump to bracket nuts 10 Nm (7 lbf.ft)
SAI pump bracket to body bolt 20 Nm (15 lbf.ft)
Vacuum reservoir to mounting bracket bolt 10 Nm (7 lbf.ft)
TORQUE DESCRIPTION METRIC IMPERIAL
ECT sensor15 Nm (11 lbf.ft)
Fuel tank cradle45 Nm (33 lbf.ft)
CKP sensor10 Nm (7 lbf.ft)
MAP and IAT sensor 10 Nm (7 lbf.ft)
Fuel cooler to inlet manifold - upper bolts 25 Nm (18 lbf.ft)
Turbocharger to exhaust manifold 30 Nm (22 lbf.ft)
Turbocharger drain pipe 10 Nm (7 lbf.ft)
Banjo bolt to oil feed pipe 25 Nm (18 lbf.ft)
Fuel temperature sensor 14 Nm (10 lbf.ft)
Pressure regulator 25 Nm (18 lbf.ft)
Glow plugs16 Nm (12 lbf.ft)
EUI clamp bolts32 Nm (24 lbf.ft)
EGR valve to exhaust manifold 10 Nm (7 lbf.ft)
EGR valve to inlet manifold 10 Nm (7 lbf.ft)
EGR clip25 Nm (18 lbf.ft)

LIFTING AND TOWING
08-2
Reverse procedure when removing vehicle from
stands.
Hydraulic ramps
Use only a 'drive on' type ramp which supports a
vehicle by it's own road wheels. If a 'wheel free'
condition is required, use a 'drive on' ramp
incorporating a 'wheel free' system that supports
under axle casings. Alternatively, place vehicle on a
firm, flat floor and support on axle stands.
TOWING
Towing
The vehicle has permanent four wheel drive. The
following towing instructions must be adhered
to:
Towing on 4 wheels with driver
Turn ignition key to position '1' to release steering
lock.
Select neutral in main gearbox and transfer gearbox.
Secure tow rope, chain or cable to towing eye.
Release the handbrake.
The brake servo and power assisted steering
system will not be functional without the engine
running. Greater pedal pressure will be required
to apply the brakes, the steering system will
require greater effort to turn the front road
wheels. The vehicle tow connection should be
used only in normal road conditions, 'snatch'
recovery should be avoided.Suspended tow
To prevent vehicle damage, front or rear
propeller shaft MUST BE removed, dependent
upon which axle is being trailed.
Mark propeller shaft drive flanges at transfer box and
axles with identification lines to enable the propeller
shaft to be refitted in its original position.
Remove the propeller shaft fixings, remove the shaft
from the vehicle.
If the front axle is to be trailed turn ignition key to
position '1' to release steering lock.
The steering wheel and/or linkage must be
secured in a straight ahead position. DO NOT use
the steering lock mechanism for this purpose.
Towing eyes
The towing eyes at the front and rear of the vehicle
are designed for vehicle recovery purposes only and
must NOT be used to tow a trailer or caravan.
Front:A single towing eye, set behind a removable
panel in the front spoiler. DO NOT use the front
lashing rings for towing.

ENGINE - TD5
12-1-12 DESCRIPTION AND OPERATION
Description
General
The Td5 diesel engine is a 2.5 litre, 5 cylinder, in-line direct injection unit having 2 valves per cylinder, operated by a
single overhead camshaft. The engine emissions, on pre EU3 models, comply with ECD2 (European Commission
Directive) and on EU3 models, comply with ECD3 legislative requirements. Both models employ electronic engine
management control, positive crankcase ventilation and exhaust gas recirculation to limit the emission of pollutants.
The unit is water cooled and turbo-charged and is controlled by an electronic engine management system.
The engine is a monobloc cast iron construction with an aluminium stiffening plate fitted to the bottom of the cylinder
block to improve lower structure rigidity. The cylinder head and sump are cast aluminium. An acoustic cover is fitted
over the upper engine to reduce engine generated noise.
The engine utilises the following features:
lElectronic Unit Injectors (EUI's) controlled by an Engine Management System for precise fuel delivery under
all prevailing operating conditions.
lTurbocharging which delivers compressed air to the combustion chambers via an intercooler for improved
power output.
lFuel Cooler
lOil Cooler
lCentrifuge Oil Filter
lHydraulic Lash Adjusters with independent finger followers
Cylinder block components
The cylinder block components are described below:
Cylinder Block
The cylinders and crankcase are contained in a single cast iron construction. The cylinders are direct bored and
plateau honed with lubrication oil supplied via lubrication jets for piston and gudgeon pin lubrication and cooling. It is
not possible to rebore the cylinder block if the cylinders become worn or damaged. Three metal core plugs are fitted
to the three centre cylinders on the right hand side of the cylinder block.
Lubrication oil is distributed throughout the block via the main oil gallery to critical moving parts through channels
bored in the block which divert oil to the main and big-end bearings via oil holes machined into the crankshaft. Oil is
also supplied from the cylinder block main gallery to the five lubrication jets which cool and lubricate the piston and
gudgeon pins. Plugs are used to seal both ends of the main oil gallery at front and rear of the engine block. An oil
cooler is fitted to the LH side of the engine block; ports in the oil cooler assembly mate with ports in the cylinder block
to facilitate coolant flow. Oil is diverted through the oil cooler, centrifuge filter and full-flow filter before supplying the
main oil gallery. A tapping in the oil filter housing provides a lubrication source for the turbocharger bearings and an
oil pressure switch is included in a tapping in the oil cooler housing which determines whether sufficient oil pressure
is available to provide engine lubrication and cooling.
Cylinder cooling is achieved by water circulating through chambers in the engine block casting. A threaded coolant
jacket plug is located at the front RH side of the cylinder block.
Cast mounting brackets are bolted to both sides of the engine block for mounting the engine to the chassis on the LH
and RH hydramount studs.
The gearbox bolts directly to the engine block; a gearbox shim plate is located between the adjoining faces of the
gearbox and the flywheel side of the engine block and is fixed to the rear of the engine block by two bolts. Two hollow
metal dowels locate the rear of the cylinder block to the gearbox shim plate. The gearbox casing provides the
mounting for the starter motor.
A port is included at the rear left hand side of the cylinder block which connects to the turbocharger oil drain pipe to
return lubrication oil to the sump.
A plug sealing the lubrication cross-drilling gallery is located at the front right hand side of the cylinder block and plugs
for the main lubrication gallery is included at the front and rear of the cylinder block.

ENGINE - TD5
DESCRIPTION AND OPERATION 12-1-15
Oil cooler
1Front oil gallery – full-flow filter to oil cooler
matrix
2Full-flow filter adaptor outlet port to oil cooler
(open at >74
° C)
3Full-flow filter inlet port
4Oil cooler housing
5Full-flow filter outlet port to cylinder block
6Coolant inlet port
7Oil cooler banjo bolt seals (2 off)
8Banjo bolts (2 off)
9Banjo bolt oil holes – to oil cooler matrix
10Rear oil gallery – full-flow filter/oil cooler outlet
to cylinder block11Centre oil gallery – from pump to full-flow filter
12Inlet port to centrifuge filter
13Sealing ring – centrifuge filter housing to oil
cooler housing
14Port – oil cooler matrix
15Oil cooler matrix
16Inlet port from pump via cylinder block to oil
cooler housing
17Outlet port from oil cooler housing to cylinder
block
18Rear view of oil cooler housing
The engine oil cooler assembly is located on the left hand side of the engine block behind the oil centrifuge and oil
filter. The housing is bolted to the engine block by seven bolts. A matrix is included in the oil cooler housing which
acts as a heat exchanger. Coolant flow circulates through the oil cooler housing under pressure from the coolant pump
and distributes the flow evenly around the matrix fins and then along the block into three core holes for cylinder
cooling. Coolant enters the oil cooler through a pipe with a rubber hose extension at the rear side of the engine. The
coolant hose is attached to the stub pipe of the oil cooler by a spring clip.
Oil drawn from the sump by the oil pump passes through the oil cooler via the cylinder block. The flow of coolant
around the exterior surface of the oil cooler matrix cools a proportion of the engine oil flow as it passes through the
oil cooler matrix.
The oil cooler is sealed to the cylinder block by a gasket which must be replaced every time the oil cooler housing is
removed.