ESP LAND ROVER DISCOVERY 1995 Workshop Manual

01INTRODUCTION
6
INFORMATION 2.Raise front road wheels to enable an axle stand
to be installed under left hand axle tube.
3.Position an axle stand under right hand axle
tube, carefully lower jack until axle sits securely
on both axle stands, remove trolley jack.
4.Before commencing work on underside of
vehicle re-check security of vehicle on stands.
5.Reverse procedure when removing vehicle from
stands.
Raise rear of vehicle
1.Position cup of hydraulic arm under differential
casing.
2.Raise vehicle to enable axle stands to be
installed under left and right hand axle tubes.
3.Lower jack until axle sits securely on axle
stands, remove trolley jack.
4.Before commencing work on underside of
vehicle re-check security of vehicle on stands.
5.Reverse procedure when removing vehicle from
stands.
HYDRAULIC VEHICLE RAMP (FOUR POST)
Use only a 'drive on' type ramp which supports vehicle
by its 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.
TWO POST VEHICLE RAMPS
The manufacturer of LAND ROVER VEHICLES
DOES NOT recommend using 'Two Post' ramps
that employ four adjustable support arms. These
are NOT considered safe for Land Rover vehicles.
If vehicle is installed on a Two Post ramp
responsibility for safety of vehicle and personnel
performing service operations is in the hands of
the Service Provider.DYNAMOMETER TESTING - NON ANTI-LOCK
BRAKE VEHICLES
Viscous coupling
The front and rear axles cannot be driven
independently due to the viscous coupling. This
eliminates the need for differential lock by
progressively locking the centre differential
automatically if slip occurs at any wheel.
WARNING: DO NOT attempt to drive
individual wheels with vehicle supported
on floor jacks or stands.
Four wheel dynamometers
Provided that front and rear dynamometer rollers are
rotating at identical speeds and that normal workshop
safety standards are applied, there is no speed
restriction during testing except any that may apply to
the tyres.
Two wheel dynamometers
IMPORTANT: Use a four wheel dynamometer for
brake testing if possible.
If brake testing on a single axle rig is necessary it
must be carried out with propeller shaft to rear axle
removed, AND neutral selected in BOTH main
gearbox and transfer gearbox. When checking brakes,
run engine at idle speed to maintain servo vacuum.
If checking engine performance, the transfer box must
be in high range and propeller shaft to stationary axle
must be removed.

04GENERAL SPECIFICATION DATA
16
INFORMATION VEHICLE WEIGHTS AND PAYLOAD
When loading a vehicle to its maximum (Gross Vehicle Weight), consideration must be taken of the unladen
vehicle weight and the distribution of the payload to ensure that axle loadings do not exceed the permitted
maximum values.
It is the customer's responsibility to limit the vehicle's payload in an appropriate manner such that neither
maximum axle loads nor Gross Vehicle Weight are exceeded.
Maximum EEC kerb weight and distribution - all optional equipment
VEHICLE WEIGHTS - Mpi
3 Door 5 Door
Front axle 930 kg......................................................................... 930 kg
Rear axle 1010 kg.......................................................................... 1055 kg
Total 1940 kg................................................................................. 1985 kg
Maximum axle weights
Front axle 1110 kg.........................................................................
Rear axle 1650 kg..........................................................................
Gross vehicle weight 2720 kg........................................................
VEHICLE WEIGHTS - V8i
Front axle 970 kg......................................................................... 970 kg
Rear axle 1010 kg.......................................................................... 1055 kg
Total 1980 kg................................................................................. 2025 kg
Maximum axle weights
Front axle 1100 kg.........................................................................
Rear axle 1650 kg..........................................................................
Gross vehicle weight 2720 kg........................................................
VEHICLE WEIGHTS - 300 Tdi
Front axle 1040 kg......................................................................... 1040 kg
Rear axle 1015 kg.......................................................................... 1060 kg
Total 2055 kg................................................................................. 2100 kg
Maximum axle weights
Front axle 1200 kg.........................................................................
Rear axle 1650 kg..........................................................................
Gross vehicle weight 2720 kg........................................................
EEC kerb weight = Unladen weight + Full fuel tank + 75 kg driver.

GENERAL FITTING REMINDERS
1
INFORMATION GENERAL FITTING REMINDERS
WORKSHOP SAFETY IS YOUR RESPONSIBILITY!
The suggestions, cautions and warnings in the
section are intended to serve as reminders for
trained and experienced mechanics. This manual
is not a course in automotive mechanics or
workshop safety.
Shop equipment, shop environment, and the use
and disposal of solvents, fluids, and chemicals
are subject to government regulations which are
intended to provide a level of safety. It is your
responsibility to know and comply with such
regulations.
PRECAUTIONS AGAINST DAMAGE
1.Always fit covers to protect fenders before
commencing work in engine compartment.
2.Cover seats and carpets, wear clean overalls
and wash hands or wear gloves before working
inside vehicle.
3.Avoid spilling hydraulic fluid or battery acid on
paint work. Wash off with water immediately if
this occurs. Use Polythene sheets to protect
carpets and seats.
4.Always use a recommended Service Tool, or a
satisfactory equivalent, where specified.
5.Protect temporarily exposed screw threads by
replacing nuts or fitting plastic caps.SAFETY PRECAUTIONS
1.Whenever possible use a lift or pit when working
beneath vehicle, in preference to jacking. Chock
wheels as well as applying parking brake.
WARNING: Do not use a pit when
removing fuel system components.
2.Never rely on a jack alone to support vehicle.
Use axle stands carefully placed at jacking
points to provide rigid support.
3.Ensure that a suitable form of fire extinguisher is
conveniently located.
4.Check that any lifting equipment used has
adequate capacity and is fully serviceable.
5.Disconnect battery negative lead.
WARNING: Do not disconnect any pipes in
air conditioning refrigeration system,
unless trained and instructed to do so. A
refrigerant is used which can cause blindness if
allowed to contact eyes.
6.Ensure that adequate ventilation is provided
when volatile degreasing agents are being used.
7.Do not apply heat in an attempt to free stiff nuts
or fittings; as well as causing damage to
protective coatings, there is a risk of damage to
electronic equipment and brake linings from
stray heat.

MAINTENANCE
19
MAINTENANCE
RESET EMISSION MAINTENANCE REMINDER -
USA
The emission maintenance reminder is designed to
activate at 52,500 and 105,000 miles respectively and
will illuminate a 'Service Engine' red warning light in
instrument binnacle.
The emission maintenance reminder must be reset
after required maintenance has been carried out and
a new tamperproof label fitted by a Land Rover of
North America dealer. This emission maintenance
reminder is part of the Emission Control System
Reset
1.The control unit is located in the passenger
footwell.
2.Identify control unit and remove from plug.
3.Remove tamperproof label to reveal access hole
for resetting.
4.Place a thin metallic probe into access hole and
momentarily electrically short between reset pins
inside unit.RECOMMENDED SERVICE ITEMS
Refer Service Schedule sheets for intervals.
Clean sunroof drain tubes, clean and lubricate guide
rails and slides.
Renew the hydraulic brake fluid.
See BRAKES,
Repair, Brake System Bleed
Renew all hydraulic brake fluid, seals, brake servo
filter and flexible hoses.
All working surfaces of the master cylinder and caliper
cylinders should be examined and renewed where
necessary.
ABS vehicles only - renew hydraulic brake fluid and
flexible hoses examine the working surfaces of the
caliper cylinders and renew the seals or cylinders
where necessary.
Air cleaner - When the vehicle is used in dusty or field
conditions or deep wading, frequent attention to the
air cleaner may be required.
ABS vehicles used extensively in arduous off-road
conditions - check the rear wheel road speed sensor
for abrasive wear.

19FUEL SYSTEM
4
DESCRIPTION AND OPERATION OPERATION
Diesel engines operate by compression ignition. The
rapid compression of air in the cylinder during the
compression cycle heats the injected fuel, causing it
to self ignite. During cold starting, automatically
controlled glow plugs assist in raising the temperature
of the compressed air to ignition point.
A cold start advance unit advances the injection timing
to further assist starting. Idle quality is improved by
the high idle setting.
The engine is supplied with pre-compressed air by a
single stage turbocharger.
Exhaust gases passing over a turbine cause it to
rotate, driving a compressor mounted on the turbine
shaft. Air drawn from the cold air intake passes, via
the air cleaner, to the turbocharger where it is
compressed. The compressed air passes to the
cylinders via an intercooler, which reduces the
temperature of the compressed air, increasing its
density.
Fuel is drawn from the tank by a mechanical lift pump
and passes to the injection pump via a filter. In
addition to removing particle contamination from the
fuel, the filter incorporates a water separator, which
removes and stores both bound and unbound water.
The injection pump meters a precisely timed, exact
quantity of fuel to the injectors in response to throttle
variations, injection timing varying with engine speed.
Any excess fuel delivered to the injection pump is not
injected, passing back to the tank via the fuel return
line.
Fuel is injected in a finely atomised form into a
pre-combustion chamber in the cylinder head where it
ignites. The burning fuel expands rapidly into the main
combustion chamber, creating extreme turbulence
which mixes the burning fuel thoroughly with the
compressed air, providing complete combustion.
Cold Starting is assisted by glow plugs, a cold start
advance unit and a high idle setting.Glow plugs
Glow plug operation is controlled by a timer unit, start
relay and resistor. When the ignition is turned on the
timer unit is energised, the glow plugs start to operate
and a warning light on the dashboard illuminates,
remaining illuminated until the glow plugs are
automatically switched off.
The length of time the glow plugs will operate is
dependent on under bonnet temperature, which is
monitored by a sensor located in the timer unit.
Starting the engine results in the power supply to the
glow plugs passing through the resistor, which
reduces their operating temperature. The glow plugs
are cut out either by the temperature sensor in the
timer, or by a microswitch on the injection pump which
operates when the throttle is depressed.
Cold start advance
The cold start advance unit is connected to the engine
cooling system via hoses. It contains a temperature
sensitive element which is retracted when cold and
pulls the advance lever, via cable, towards the rear of
the pump against spring pressure. As coolant
temperature rises, the cold start element expands
releasing tension on the cable and allowing spring
pressure to move the advance lever forwards.

Tdi
9
DESCRIPTION AND OPERATION OPERATION EDC
Under start up conditions, signals from the crank
speed and water temperature sensors are relayed to
the ECM to control starting fuel quantity and injection
timing. Once the engine has started the ECM initiates
a 'closed loop' monitoring system for fuel quantity,
injector timing and EGR relative to the appropriate
engine operating conditions.
As driver demand increases, signals from the throttle
position sensor are received by the ECM together with
crank speed and position pulses. The ECM signals
the injection pump to adjust fuel quantity and timing
relative to driver demand.
As engine coolant, fuel and air temperature changes
the ECM will correct fuel delivery and injection timing
for more efficient and accurate running. The ECM will
also make corrections for atmospheric pressure on
injection timing and EGR.
Electronic Control Unit (ECM)
The EDC system is controlled by the ECM located in
the drivers footwell on the 'A' post beneath the fascia.
The unit consists of a microprocessor with integrated
circuits and components and is connected to the main
harness by a 55 pin plug.
Inputs to the ECM from engine sensors control start of
injection, injected fuel quantity, fuel cut-off and EGR.
The ECM will also make corrections for engine
coolant, fuel and air temperature and atmospheric
pressure.Injection pump
The injection pump incorporates actuator controlled
injected fuel quantity and solenoid operated timing
which operate in response to ECM signals against
driver demand, engine speed, temperature and boost
pressure.
A fuel cut-off facility and fuel temperature sensor is
incorporated in the pump.
Injection timing sensor
An inductive sensor in No 4 injector body monitors
needle movement. This forms part of a 'closed loop'
system to control start of injection.
The system measures timing, relating the needle
movement signal to crank position (determined by
flywheel pulses from the engine speed sensor).
Air flow sensor
The Air Flow Sensor is mounted on a bracket
attached to the wheel arch valance, and connected by
hose to the air cleaner and turbo charger inlet.
The unit consists of a flap valve airflow sensor which
measures the fresh air flow into the engine. The
sensor informs the ECM and, provided that the other
conditions are met, will implement EGR.
Engine speed sensor
The engine speed sensor is an active inductive sensor
mounted on the flywheel housing. Pulses from the
sensor activated by radial slots in the flywheel give
engine speed and position information to the ECM.

19FUEL SYSTEM
10
DESCRIPTION AND OPERATION Vehicle speed sensor
The vehicle speed sensor is located on the transfer
box behind the transmission brake. The unit has a
multirole as the vehicle electronic speedometer
sensor and as a sensor for 'surge damping', (a
function which smooths out engine response to sharp
accelerator movement and reduces vehicle 'bucking').
The sensor is an additional input for engine overheat
protection.
Brake and clutch switches
The brake and clutch switches are located on the
pedal box and serve as safety features to the system.
They return information to the ECM which limits
maximum fuel quantity under braking.
Throttle position sensor
The accelerator pedal is connected directly to a
sensor mounted in the pedal box. Driver demand is
relayed back to the ECM to increase or decrease
injected fuel quantity.
Incorporated in the sensor is a backup idle switch
which the system will default to in the event of sensor
failure.
Boost pressure sensor
The boost pressure sensor is mounted on the
bulkhead. It relays boost pressure information to the
ECM which compensates fuel quantity to reduce
smoke during acceleration.
Electro-pneumatic modulator
The electro-pneumatic modulator is located on the
inner wing just forward of the air cleaner. It regulates
vacuum signals from the source to the EGR valve.
The ECM controls the modulator to open the EGR
valve according to required airflow.Exhaust gas recirculation valve
The EGR valve is located on the engine exhaust
manifold and is controlled by vacuum from the
electro-pneumatic modulator.
Once open the EGR valve directs a quantity of
exhaust gas back into the inlet manifold to be burnt
inside the engine. This reduces NOx (Oxides of
nitrogen) emissions of the engine.
Temperature sensors
Water, Fuel and Air temperature sensors monitor
engine conditions and relay their information back to
the ECM which makes adjustments to injected fuel
quantity, injection timing, EGR and corrections to
measured boost pressure and airflow.

MFI
1
DESCRIPTION AND OPERATION DESCRIPTION
Hot Wire Multiport Fuel Injection
The 'Hot Wire' Multiport fuel injection system derives
its name from the mass air flow sensor which uses
one cold wire and one electrically heated wire to
measure the volume of air entering the engine.
The function of the system is to supply the exact
amount of fuel directly into the intake manifold
according to the prevailing engine operating
conditions.
To monitor these conditions, various sensors are fitted
to the engine to measure engine parameters. Data
from the sensors is received by the Engine control
module (ECM), the ECM will then determine the exact
amount of fuel required at any condition.
The ECM having received data from the sensors
produces pulses, the length of which will determine
the simultaneous open time of each bank of injectors
in turn, which will govern the amount of fuel injected.
Engine control module - ECM
The Multiport fuel injection system is controlled by the
14 CUX Engine Control Module comprising of a
microprocessor with integrated circuits and
components mounted on printed circuit boards. The
ECM is connected to the main harness by a 40 pin
plug.
Injectors
The eight fuel injectors are fitted between the
pressurized fuel rail and inlet manifold. Each injector
comprises a solenoid operated needle valve with a
movable plunger rigidly attached to the nozzle valve.
When the solenoid is energized the plunger is
attracted off its seat and allows pressurized fuel into
the intake manifold.Engine coolant temperature sensor
The engine coolant temperature sensor is located in
the front of the thermostat housing. The sensor
provides engine coolant information to the ECM. The
ECM increases the injector opening time when cold to
provide improved driveability, and reduces the
opening time as the engine reaches normal operating
temperature.
Engine fuel temperature sensor
The engine fuel temperature sensor is located in the
rail on the RH side of the ram housing. The sensor
sends fuel temperature data to the ECM, the ECM on
receiving the data will adjust the injector open time
accordingly to produce good hot starting in high
ambient temperatures.
Idle air control valve
The idle air control valve is screwed into a housing
attached to the rear of the plenum chamber, between
the plenum chamber and bulkhead. The idle air
control valve has two windings which enable the
motor to be energised in both directions thus opening
or closing the air valve as required by the ECM.
The idle air control valve will open and allow extra air
into the plenum chamber to maintain engine idle
speed when the engine is under increased (Electrical
and Mechanical) loads.
The idle air control valve will control engine idle speed
when the vehicle is stationary.
Heated oxygen sensors (0
2sensors) - Catalyst
vehicles
The two heated oxygen sensors are located forward
of the catalysts mounted in the exhaust downpipes.
The sensors monitor the oxygen content of the
exhaust gases and provide feedback information of
the air/fuel ratio to the ECM. Each sensor is heated by
an electrical element to improve its response time
when the ignition is switched on.

19FUEL SYSTEM
2
DESCRIPTION AND OPERATION Fuel pressure regulator
The fuel pressure regulator is mounted in the fuel rail
at the rear of the plenum chamber. The regulator is a
mechanical device controlled by plenum chamber
vacuum, it ensures that fuel rail pressure is
maintained at a constant pressure difference of 2.5
bar above that of the manifold.
When pressure exceeds the regulator setting excess
fuel is returned to the fuel tank.
Fuel pump
The electric fuel pump is located in the fuel tank, and
is a self priming 'wet' pump, the motor is immersed in
the fuel within the tank.
Air flow sensor
The hot-wire air flow sensor is mounted on a bracket
attached to the left hand valance, rigidly connected to
the air cleaner and by hose to the plenum chamber
inlet neck.
The air flow sensor consists of a cast alloy body
through which air flows. A proportion of this air flows
through a bypass in which two wire elements are
situated: one is a sensing wire and the other is a
compensating wire. Under the control of an electronic
module which is mounted on the air flow sensor body,
a small current is passed through the sensing wire to
produce a heating effect. The compensating wire is
also connected to the module but is not heated, but
reacts to the temperature of the air taken in, as engine
intake air passes over the wires a cooling effect takes
place.
The electronic module monitors the reaction of the
wires in proportion to the air stream and provides
output signals in proportion to the air mass flow rate
which are compatible with the requirements of the
ECM.Throttle position sensor
The throttle position sensor is mounted on the side of
the plenum chamber inlet neck and is directly coupled
to the throttle butterfly shaft.
The throttle position sensor is a resistive device
supplied with a voltage from the ECM. Movement of
the accelerator pedal causes the throttle valve to
open, thus rotating the wiper arm within the throttle
position sensor which in turn varies the resistance in
proportion to the valve position. The ECM lengthens
the injector open time when it detects a change in
output voltage (rising) from the throttle position
sensor.
In addition the ECM will weaken the mixture when it
detects the throttle position sensor output voltage is
decreasing under deceleration and will shorten the
length of time the injectors are open.
When the throttle is fully open, the ECM will detect the
corresponding throttle position sensor voltage and will
apply full load enrichment. This is a fixed percentage
and is independent of temperature. Full load
enrichment is also achieved by adjusting the length of
the injector open time.
When the throttle is closed, overrun fuel cut off or idle
speed control may be facilitated dependant on other
inputs to the ECM.
The throttle position sensor is 'self adaptive', which
means that adjustment is not possible. It also means
the throttle position sensor setting is not lost, for
example, when throttle stop wear occurs.
CAUTION: Do not attempt to adjust throttle
position sensor.

SFI
1
DESCRIPTION AND OPERATION ENGINE MANAGEMENT SYSTEM
Description
The engine management system (EMS) maintains
optimum engine performance over the entire
operating range. The correct amount of fuel is
metered into each cylinder inlet tract and the ignition
timing is adjusted at each spark plug.
The system is controlled by the ENGINE CONTROL
MODULE (ECM) which receives data from sensors
located on and around the engine. From this
information it provides the correct fuel requirements
and ignition timing at all engine loads and speeds.
The fuel injection system uses a hot wire Mass Air
Flow Sensor to calculate the amount of air flowing into
the engine.
The ignition system does not use a distributor. It is a
direct ignition system (DIS), using four double ended
coils. The circuit to each coil is completed by
switching inside the ECM.
The on board diagnostic system detects any faults
which may occur within the EMS. Fault diagnosis
includes failure of all EMS sensors and actuators,
emissions related items, fuel supply and exhaust
systems.
The system incorporates certain default strategies to
enable the vehicle to be driven in case of sensor
failure. This may mean that a fault is not detected by
the driver. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.
A further feature of the system is 'robust
immobilisation'.Crankshaft position sensor (CKP Sensor)
The crankshaft position sensor is the most important
sensor on the engine. It is located in the left hand side
of the flywheel housing and uses a different thickness
of spacer for manual and automatic gearboxes. The
signal it produces informs the ECM:
- the engine is turning
- how fast the engine is turning
- which stage the engine is at in the cycle.
As there is no default strategy, failure of the
crankshaft sensor will result in the engine failing to
start. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.
Camshaft position sensor (CMP Sensor)
The camshaft position sensor is located in the engine
front cover. It produces one pulse every two
revolutions. The signal is used in two areas, injector
timing corrections for fully sequential fuelling and
active knock control.
If the camshaft sensor fails, default operation is to
continue normal ignition timing. The fuel injectors will
be actuated sequentially, timing the injection with
respect to top dead centre. Injection will either be
correct or one revolution out of synchronisation. The
fault is not easily detected by the driver. The fault is
indicated by illumination of the malfunction indicator
light (MIL) on North American specification vehicles.
Mass air flow sensor (MAF Sensor)
The 'hot wire' type mass air flow sensor is mounted
rigidly to the air filter and connected by flexible hose to
the plenum chamber inlet. The sensing element of the
MAF Sensor is a hot wire anenometer consisting of
two wires, a sensing wire which is heated and a
compensating wire which is not heated. Air flows
across the wires cooling the heated one, changing its
resistance. The ECM measures this change in
resistance and calculates the amount of air flowing
into the engine.
As there is no default strategy, failure will result in the
engine starting, and dying when it reaches 550
rev/min, when the ECM detects no MAF Sensor
signal. The fault is indicated by illumination of the
malfunction indicator light (MIL) on North American
specification vehicles.