heater LAND ROVER DISCOVERY 1995 User Guide

V8i
13
REPAIR
NOTE: Release bolts securing compressor
mounting bracket to engine and remove
bracket to enable temporary lifting eye
ETC 5964 to be fitted. Secure lifting eye to
mounting bracket fixing points with suitable bolts
of equivalent size, pitch and thread. Leave lifting
eye attached until engine is reinstalled in vehicle.
15.Place drain tray underneath vehicle.
16.Disconnect hose from reservoir to power
steering pump. Secure hose end above level of
fluid reservoir to avoid unnecessary loss of fluid.
17.Disconnect power steering pump to power
steering box hose. Seal hose and pump
openings with masking tape to prevent ingress of
dirt. Wipe away any fluid spillage from chassis or
steering box.
18.Disconnect fuel temperature and coolant
temperature sensor multi-plugs.
19.Disconnect leads from coil.
20.Identify each injector multi-plug for re-assembly
and disconnect plugs from injectors.
21.Manoeuvre harness from behind fuel rails and
place to one side clear of engine assembly.
22.Remove two clamps securing gearbox oil cooler
pipes to engine block.
23.Remove engine mounting fixings on both sides
of cylinder block.
24.Fit lifting chains to engine lifting eyes as shown
in illustration RR1780E.
1. L/H Front chain 356mm total overall length.
2. R/H Front chain 330mm total overall length.
3. R/H Rear chain 457mm total overall length.
NOTE: All chain dimensions are measured
from end of lifting hook to end of last link
in chain.
25.Fit chain lifting eye to a suitable engine hoist.
Raise hoist high enough to enable engine
mountings to be removed, and withdraw rubber
mountings.
26.Lower hoist until engine rests securely on engine
mounting brackets. Remove lifting chains and
hoist.
27.Disconnect two heater hoses located on top of
right hand rocker cover.
28.Remove ground strap from rear of left hand
cylinder head. DO NOT remove from retaining
clip.
29.Remove all electrical harnesses from retaining
clips at rear of engine.
30.Remove transmission breather pipes from
retaining clip on rear lifting eye.
31.Remove top two bolts securing bell housing to
cylinder block.
32.Raise front of vehicle, lower vehicle on to axle
stands.
33.Remove bell housing bottom cover. Remove
gasket from bell housing face.
34.Remove nuts securing exhaust downpipes to
manifolds, remove heat shield from right hand
side downpipe.
35.Remove electrical leads from starter motor
solenoid. Disconnect multi-plug from oil level
sensor on side of sump, if fitted.
NOTE: Instructions 37, 38 and 39 refer to
automatic vehicles only.
36.With assistance rotate engine at crankshaft
pulley until two access holes in drive plate/ring
gear assembly are visible.
37.Remove two bolts visible through access holes.
Mark one access hole and one bolt hole to
ensure unit is reassembled in its original position
38.Rotate crankshaft 180Ê until two remaining
access holes are visible, remove two bolts.

4.0 V8
3
REPAIR ENGINE ASSEMBLY
Service repair no - 12.41.01/99
Remove
1.Position vehicle on ramp.
2.Remove bonnet.
See CHASSIS AND BODY,Repair, Bonnet [Hood]
3.Remove radiator.See COOLING SYSTEM,
Repair, Radiator
4.Remove plenum chamber.See FUEL SYSTEM
SFI, Repair, Plenum Chamber
5.Remove mass air flow sensor.See FUEL
SYSTEM SFI, Repair, Mass Air Flow Sensor
(MAF Sensor)
6.Slacken hose clip securing bottom hose to
expansion tank.
7.Disconnect hose.
8.Remove 2 nuts securing expansion tank.
9.Remove nut and bolt securing expansion tank.
10.Remove expansion tank.
11.Disconnect servo vacuum hose from ram
housing.
12.Disconnect battery sensing lead Lucar from
generator.
13.Remove generator terminal cover.
14.Remove 2 terminal nuts and release leads from
terminals.
15.Release purge hose from ram pipe housing.
16.Position cloth to absorb fuel spillage.
17.Slacken clip securing fuel return hose to fuel rail.
18.Disconnect hose.
19.Plug connections.
20.Disconnect fuel feed hose union.
21.Plug connections. Position hoses aside.
22.Slacken clip securing heater return hose to pipe.
23.Disconnect hose.24.Slacken clip securing heater feed adaptor hose
to inlet manifold.
25.Remove bolt securing pipe bracket.
26.Disconnect feed hose from inlet manifold.
27.Disconnect hose/pipe assembly.
28.Disconnect leads from spark plugs and remove
ignition coils.
See FUEL SYSTEM SFI, Repair,
Ignition Coils
29.Disconnect fuel temperature sensor multiplug.
30.Disconnect coolant sensor multiplug.
31.Disconnect temperature gauge sensor lead.
32.Release camshaft sensor multiplug from bracket
and disconnect multiplug.
33.Disconnect oil pressure switch Lucar.
34.Disconnect air intake temperature sensor
multiplug.
35.Disconnect 8 injector multiplugs.
36.Remove 4 nuts securing harness brackets to
inlet manifold.
37.Release harness brackets.
38.Remove bolts securing gearbox breather pipes
to engine lifting bracket.

4.0 V8
7
REPAIR 171.Route drive belt around pulleys.
172.Pivot tensioner downwards.
173.Align belt to tensioner and release tensioner.
174.Connect battery positive lead and tighten.
175.Secure terminal cover.
176.Align gearbox breather pipe, clip to engine lifting
eye and fit bolt. Tighten to
9 Nm.
177.Align and secure engine harness brackets to
inlet manifold and fit nuts. Tighten to
9 Nm.
178.Connect injector multiplugs.
179.Connect air intake temperature sensor multiplug.
180.Connect fuel temperature sensor multiplug.
181.Connect coolant temperature multiplug.
182.Connect temperature gauge connector.
183.Connect oil pressure switch Lucar.
184.Connect camshaft sensor multiplug and secure
to bracket.
185.Fit ignition coil bracket.
See FUEL SYSTEM
SFI, Repair, Ignition Coils
186.Position heater hose/pipe assembly.
187.Connect hose to inlet manifold.
188.Align pipe to bracket and fit bolt. Tighten to
9
Nm.
189.Tighten hose clip.
190.Connect heater return hose and tighten clip.
191.Remove plugs from fuel feed and return hose
connections.
192.Clean feed unions.
193.Connect return hose and tighten clip.
194.Connect feed hose union and tighten.
195.Remove cloth.
196.Connect purge hose.
197.Connect leads to generator, tighten terminal nuts
and fit cover.
198.Connect sensing Lucar.
199.Connect servo vacuum hose.
200.Position expansion tank and secure with fixings.
201.Connect hose and tighten clip.
202.Lower ramp.
203.Fit mass air flow sensor.
See FUEL SYSTEM
SFI, Repair, Mass Air Flow Sensor (MAF
Sensor)
204.Fit plenum chamber.See FUEL SYSTEM SFI,
Repair, Plenum Chamber
205.Fit radiator.See COOLING SYSTEM, Repair,
Radiator
206.Fit bonnet.See CHASSIS AND BODY, Repair,
Bonnet [Hood]
207.Reconnect battery negative lead.
208.Bleed power steering system.
See STEERING,
Repair, Power Steering System - Bleed
209.Drain engine oil and refill.See LUBRICANTS,
FLUIDS AND CAPACITIES, Information,
Recommended Lubricants and Fluids - USA
Vehicles
210.Start engine. Check for fuel, coolant and oil
leaks.FRONT COVER GASKET
Service repair no - 12.65.04 - Front Cover Gasket
Remove
1.Disconnect battery negative lead.
2.Drain cooling system.
See COOLING SYSTEM
V8, Adjustment, Coolant
3.Remove radiatorSee COOLING SYSTEM,
Repair, Radiator
4.Remove water pump pulley.See COOLING
SYSTEM, Repair, Viscous Coupling, Fan
Blades, Pulley and Fan Cowl
5.Slacken bottom hose clip. Remove hose from
water pump.
6.Raise vehicle on ramp.
7.Disconnect oil cooler hoses from front cover and
position aside. Plug hoses and connections.
8.Disconnect Lucar from oil pressure switch.

12ENGINE
6
REPAIR ENGINE
Service repair no - 12.41.01
Remove
1.Site vehicle onto ramp [hoist].
2.Remove the drive belt.
See SECTION 10,
Maintenance, Under Bonnet [Hood]
Maintenance
3.Remove radiator.See COOLING SYSTEM,
Repair, Radiator - Mpi
4.Remove bonnet [hood].See CHASSIS AND
BODY, Repair, Bonnet [Hood]
5.Drain engine oil.
6.Position absorbent cloth around fuel pipe to fuel
rail union.
Unscrew union to relieve pressure.
CAUTION: Plug the connections
7.Release clip and disconnect hose from coolant
pump.
8.Release clip and disconnect hose from heater
rail.

Mpi
13
REPAIR 19.Connect crankshaft sensor, knock sensor, air
conditioning compressor, fuel injector harness,
inlet manifold air temperature and fuel
temperature sensor multiplugs.
20.Connect fuel hose to pressure regulator and
secure with clip.
21.Fit and tighten fuel pipe to fuel rail union.
22.Connect multiplugs to throttle housing.
23.Connect vacuum hose to manifold.
24.Connect oil pressure switch multiplug.
25.Connect brake servo hose to manifold, secure
with clip.
26.Connect throttle cable to cam.
27.Position engine harness and connect breather
hose to inlet manifold, secure with clip.
28.Connect coolant temperature sensor multiplugs,
secure harness with cable tie.
29.Connect oxygen sensor multiplug, secure
harness with cable tie.
30.Connect alternator harness.
31.Connect heater hose to heater rail and secure
with clip.
32.Connect hose to coolant pump and secure with
clip.
33.Connect inlet hose to power steering pump and
secure with clip.
34.Fit and tighten outlet pipe union to power
steering pump.
35.Connect bypass and top hose, secure with clip.
36.Connect air cleaner to throttle housing hose and
secure with clip.
37.Remove engine lifting bracket.
38.Position spark plug cover and secure with
screws.
39.Fill engine with oil.
40.Fit bonnet [hood].
See CHASSIS AND BODY,
Repair, Bonnet [Hood]
41.Fit radiator.See COOLING SYSTEM, Repair,
Radiator - Mpi
42.Adjust throttle cable.See FUEL SYSTEM,
Adjustment, Throttle Cable Adjustment
ENGINE SUMP GASKET
Service repair no - 12.60.43
Remove
1.Drain engine oil.
2.Refit drain plug, use new sealing washer if
necessary, tighten to the correct torque.
3.Remove 18 bolts securing sump.
NOTE: 25mm long bolt is fitted at rear L.H.
corner of sump.
4.Release sump from cylinder block.
5.Discard gasket.

Mpi
15
REPAIR 4.Release clip and disconnect hose from heater
rail.
5.Disconnect 2 coolant temperature sensor
multiplugs.
6.Release clips and disconnect the bypass hose
and top hose.
7.Release harness from cable tie.
8.Disconnect oxygen sensor multiplug.
9.Release harness lead from cable tie.
10.Release throttle cable from abutment bracket.
11.Release throttle cable from cam. Also remove
coolant bypass hose from throttle housing.
12.Disconnect stepper motor and throttle
potentiometer multiplugs.
13.Release clip and disconnect hose, air cleaner to
throttle housing.

12ENGINE
18
REPAIR Refit
1.Fit location dowels to cylinder head.
2.Fit cylinder head gasket to cylinder block.
3.Using assistance fit cylinder head to cylinder
block.
4.Lubricate cylinder head bolts.
5.Fit and tighten cylinder head bolts to the correct
torque and in the correct sequence.
NOTE: For torque values.See
Specifications, torque, Torque values
6.Fit timing belt.
7.Fit camshaft covers.
8.Fit spark plug leads to spark plugs and secure to
clips.
9.Fit spark plug cover and secure with screws.
10.Fit new gasket and secure downpipe to exhaust
manifold with nuts.
11.Fit bolt securing dipstick tube to coolant rail.
12.Connect 3 vacuum hoses to inlet manifold.
13.Connect fuel to pressure regulator, secure with
clip.
14.Connect fuel injection harness, inlet manifold air
temperature sensor and fuel temperature sensor
multiplugs.
15.Secure engine harness to manifold with bolts.
16.Connect brake servo hose to manifold, secure
with clip.
17.Connect air cleaner hose to throttle housing,
secure with clip.
18.Connect stepper motor and throttle
potentiometer multiplugs.
19.Fit and adjust throttle cable.
20.Connect oxygen sensor multiplug, secure with
cable tie.
21.Connect the bypass and top hose, secure with
clips.
22.Connect coolant temperature sensor multiplugs,
secure with cable tie.
23.Connect hose to heater rail and secure with clip.
24.Connect radiator bottom hose and secure with
clip.
25.Tighten fuel pipe to fuel rail union.
26.Reconnect battery negative lead.

19FUEL SYSTEM
8
REPAIR 10.Remove fuel rail and injectors.
11.Remove injector retaining clips, ease injectors
from rail. Remove and discard 'O' rings from
injectors.
12.Remove fuel pressure regulator if required.
Refit
13.FitNEW'O' rings, to injectors. Lightly coat 'O'
rings with silicon grease 300. Insert injectors into
fuel rail, multi-plug connections facing outwards.
14.Refit retaining clips.
CAUTION: Care must be taken when
refitting the fuel rail and injectors to intake
manifold to prevent damage to 'O' rings.
15.Fit aNEW'O' ring to pressure regulator lightly
coat 'O' ring with silicon grease 300 and secure
regulator to the fuel rail.
16.Fit fuel rail and heater pipe assemblies to intake
manifold. Secure rail and pipes in position with
five bolts.
17.Reverse removal procedure. 2 to 7.
18.Pressurise fuel system and check for fuel leaks
around injectors and pressure regulator.PLENUM CHAMBER
Service repair no - 19.22.46
Includes throttle levers and throttle disc
Remove
1.Disconnect battery negative lead.
2.Disconnect electrical multi-plug from bypass air
valve.
3.Disconnect vacuum hose adjacent to bypass air
valve.
4.Mark an identification line on throttle cable outer
to assist re-assembly.
5.Remove clevis pin from throttle cable.
6.Pry adjustment thumb wheel from throttle
bracket. Lay cable aside.
7.Remove retaining clip and clevis pin from kick
down cable (automatic vehicles).
8.Apply adhesive tape behind rear adjustment nut
on kick down cable to prevent nut moving.
9.Remove front lock nut. Remove cable and lay
aside.
10.Remove cruise control vacuum hose.
11.Remove intake hose from neck of plenum
chamber.
12.Disconnect throttle position sensor multi-plug.
13.Remove PCV breather hose.
14.Disconnect two coolant hoses and plug each
hose to prevent excessive loss of coolant.
Identify each hose for re-assembly.

MFI
15
REPAIR 11.Loosen clip and disconnect top hose from
thermostat housing.
12.Disconnect multiplug from distributor amplifier
module.
13.Loosen clip and disconnect hose from heater
valve.
14.Remove injector harnesses from behind fuel rail
and lay to one side.
15.Loosen union and disconnect fuel return hose
from fuel rail.
NOTE: The intake manifold can be
removed from the cylinder block without
removing the fuel rail and injectors.
16.Using the sequence shown, remove 12 bolts
securing the intake manifold to cylinder block.
17.Remove the intake manifold.
18.Noting their fitted position, remove bolts and
clamps securing intake manifold gasket to
cylinder block.
19.Remove and discard gasket.
20.Remove and discard gasket seals.
Do not carry out further dismantling if component
is removed for access only.
21.Remove 5 nuts securing fuel rail support
brackets to intake manifold.
22.Remove fuel rail and injectors.
23.Remove 2 bolts securing thermostat housing to
intake manifold.
24.Remove thermostat housing.
25.Remove bolt securing coolant pipe to intake
manifold. Loosen union and remove coolant
pipe. Remove and discard 'O' ring.
26.Fit new 'O' ring to coolant pipe. Position coolant
pipe to intake manifold. Fit bolt securing coolant
pipe support bracket to intake manifold and
tighten pipe union.
27.Clean mating faces of thermostat housing and
intake manifold.
28.Fit thermostat housing to intake manifold using a
new gasket, fit and tighten bolts.
29.Position fuel rail to intake manifold, fit and
tighten retaining bolts.

Mpi
5
DESCRIPTION AND OPERATION
Fuel pump
The electric fuel pump, located inside the fuel tank, is
a self-priming centrifugal 'wet' pump, the motor and
pump are filled with fuel.
The fuel pump supplies more fuel than the maximum
load requirement for the engine, so that pressure in
the fuel system can be maintained under all
conditions.
Fuel pressure regulator
The pressure regulator is a mechanical device
controlled by manifold depression and is mounted in
the fuel rail. The regulator ensures that fuel rail
pressure is maintained at a constant pressure
difference to that in the inlet manifold, as manifold
depression increases the regulated fuel pressure is
reduced in direct proportion.
When pressure exceeds the regulator setting excess
fuel is spill returned to the fuel tank swirl pot which
contains the fuel pick-up strainer.
Relay module
The relay module contains the main relay, fuel pump
relay, starter relay and oxygen sensor relay and is
mounted on the ECM mounting bracket.
The main relay is energised when the ignition is
switched on and supplies current to the ECM
The fuel pump relay is energised by the ECM for a
short period when the ignition is switched on, during
cranking and while the engine is running.
The starter relay is energised by the cranking signal
from the ignition switch.
This oxygen sensor relay is energised when the
ignition is switched on and supplies current to the
ECM
Intake air temperature sensor
The intake air temperature sensor is fitted in the side
of the inlet manifold and sends the ECM a signal
relating to air temperature. The ECM uses this signal
in its calculations on air flow.
Inertia switch
The fuel pump circuit incorporates an inertia switch
which in the event of sudden deceleration isolates the
power supply to the fuel pump. The inertia switch is
situated in the engine compartment on the bulkhead
and can, if tripped, be reset by depressing the central
plunger.
WARNING: Check the integrity of the fuel
system before the inertia switch is reset.
Diagnostic connector
A diagnostic connector is provided to enable
diagnosis to be carried out without disturbing the
system electrical connections and to allow the ECM's
ability to store certain faults to be utilised.
Oxygen sensor - Closed-loop emission control
The MEMS Mpi system operates a closed loop
emission system to ensure the most efficient level of
exhaust gas conversion.
An oxygen sensor fitted in the exhaust manifold
monitors the exhaust gases. It then supplies a small
voltage proportional to exhaust oxygen content to the
ECM As the air/fuel mixture weakens, the exhaust
oxygen content increases and so the voltage to the
ECM decreases. If the mixture becomes richer so the
oxygen content decreases and the voltage increases.
The ECM uses this signal voltage to determine the
air/fuel mixture being delivered to the engine, and
adjusts the injector duration to maintain the ratio
necessary for efficient gas conversion by the catalyst.
The oxygen sensor has an integral heating element to
ensure an efficient operating temperature is quickly
reached from cold. The electrical supply for the heater
element is controlled by the oxygen sensor relay.
Fuel temperature sensor
The fuel temperature sensor is inserted in the fuel rail
and measures fuel and fuel rail temperatures. During
engine cranking at high temperatures, the ECM
increases fuel supply, and opens the throttle disc via
the stepper motor to aid hot starting.