Anti theft JAGUAR XJ6 1997 2.G User Guide

pull loose, tap it with a soft-faced hammer. Do
not use a screwdriver between the cover and
the thermostat housing.
8Remove the thermostat, noting the
direction in which it was installed in the
housing, and thoroughly clean the sealing
surfaces.
9Refit a new O-ring onto the thermostat (see
illustration). Make sure it is evenly fitted all
the way around.
10Apply a bead of RTV sealant to the
thermostat housing. Refit the thermostat and
housing, positioning the jiggle pin at the
highest point. Note:The thermostat is usually
marked TOP on the radiator side for proper
orientation.
11Tighten the cover fasteners to the torque
listed in this Chapter’s Specifications.
12Refill the cooling system, run the engine
and check for leaks and proper operation.
4 Engine cooling fans-
check and renewal
3
Mechanical fan
(1988 to 1992 models)
Warning: Keep hands, hair, tools
and clothing away from the fan
when the engine is running. Toavoid injury or damage DO NOT operate
the engine with a damaged fan. Do not
attempt to repair fan blades - renew a
damaged fan .
Check
Warning: In order to check the
fan clutch, the engine will need
to be at operating temperature,
so while going through checks
prior to Step 6 be careful that the ignition is
NOT switched on. Severe personal injury
can result!
1Symptoms of failure of the fan clutch are
continuous noisy operation, looseness,
vibration and evidence of silicone fluid leaks.
2Rock the fan back and forth by hand to
check for excessive bearing play.
3With the engine cold, turn the blades by
hand. The fan should turn freely.
4Visually inspect for substantial fluid leakage
from the fan clutch assembly, a deformed bi-
metal spring or grease leakage from the
cooling fan bearing. If any of these conditions
exist, renew the fan clutch.
5When the engine is fully warmed up, turn off
the ignition switch and disconnect the cable
from the negative battery terminal. Turn the
fan by hand. Some resistance should be felt. If
the fan turns easily, renew the fan clutch.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, makesure you have the correct activation code
before disconnecting the battery.
Removal and refitting
6Leave the battery cable disconnected (see
the Caution in Step 5).
7Remove the fan’s drivebelt (see Chapter 1).
8Remove the nuts holding the fan assembly
to the water pump (see illustration). Note:
You’ll have to “walk” the fan assembly forward
as you loosen the nuts. There is not enough
room to remove them all the way at one time.
9The fan can be removed without removing
the shroud, if you are only renewing the fan or
clutch (see illustration). Be careful not to
allow the blades contact the radiator fins.
10Remove the two fan shroud mounting
clips at the top of the shroud (see illustration).
11Lift the shroud up and out of the engine
compartment. The bottom of the fan shroud
does not have any fasteners. It has two tangs
on the bottom that slip out of slots in the body
when pulled up.
12The fan clutch can be unbolted from the
fan blade assembly for renewal (see
illustration).
Caution: To prevent silicone fluid from
draining from the clutch assembly into the
fan drive bearing and ruining the lubricant,
DON’T place the clutch in a position with
the rear pointing down. Store the clutch in
its upright position if possible.
Cooling, heating and air conditioning systems 3•3
3
4.9 The fan can be removed with the
shroud in place by angling it out of
the shroud4.10 Pry out the two clips (arrow indicates
the left one) at the top of the fan shroud
and lift out the shroud
3261 Jaguar XJ6 3.9 The thermostat is fitted with the spring end towards the
cylinder head - use a new O-ring (A) and position jiggle pin (B) up
4.8 Remove the four nuts (arrows indicate three shown here)
holding the fan/clutch assembly to the front of the water pump
4.12 Separate the fan clutch from the fan
by removing the four bolts (arrowed)

13Refitting is the reverse of removal. Tighten
the fan clutch-to-fan blade bolts and the fan
assembly-to-drive hub nut to the torque listed
in this Chapter’s Specifications.
Electric fans
Check
Warning: Keep your hands or
clothing away from the fan
blades at all times.
14On 1988 through 1992 models, a single
electric fan is mounted in front of the radiator,
controlled by a thermostatic switch. Access to
the fan is with the grille removed. The 1993
and 1994 models have a fan shroud assembly
that includes two electric fans, and a “twin”
thermostatic switch, with the assembly
mounted on the engine side of the radiator.
15If the electric fan does not come on at any
time, bypass the thermostatic switch by
disconnecting the electrical connector at the
switch and connecting the two pins with a
jumper wire (see illustration). If the fan now
operates, renew the thermostatic switch. If the
fan doesn’t operate, the problem is either the
fan relay or the fan motor. On 1993 and 1994
models with twin electric fans, jumpering one
set of connections in the plug from the switch
should make both fans operate at slow speed
(fans in series) and jumpering the other two
should run both fans at higher speed (fans in
parallel). In normal operation, the fans operate
at the higher-speed only when the air
conditioning is on, or when coolant
temperature exceeds 212° F. When the
coolant cools down to below 200° F, the fans
revert to the normal speed.
16To renew a defective thermostatic switch,
allow the vehicle to cool off and drain the
coolant (see Chapter 1). Remove the switch
from the radiator and refit the new switch.
Connect the electrical connector and test
again for proper fan operation.17To test an inoperative fan motor (one that
doesn’t come on when the engine gets hot or
when the air conditioner is on), first check the
fuses and/or fusible links (see Chapter 12).
Then disconnect the electrical connector at
the motor (refer to Chapter 11 for removal of
the grille for access on front-mounted-fan
models) and use fused jumper wires to
connect the fan directly to the battery and to
chassis ground (see illustration). If the fan
still does not work, renew the fan motor.
Warning: Do not allow the test
clips to contact each other or
any metallic part of the vehicle.
18If the motor tested OK in the previous test
but is still inoperative, then the fault lies in the
relay, fuse, or wiring. The fan relay can be
tested for continuity (see Chapter 12).
Renewal
19Disconnect the negative battery cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.20Access the 1988 through 1992 single
electric fan with the grille removed (see
Chapter 11 for grille removal). Disconnect the
electrical connector and remove the bolts
holding the fan assembly to the body (see
illustration).
21On 1993 and 1994 models, remove the
two bolts holding the fan shroud to the top of
the radiator and lift the shroud/fans assembly
from the vehicle.
22If the fan on 1988 to 1992 models must be
renewed, renew the fan, motor and shroud as
a unit. The fan is separate from the shroud on
later models.
23Refitting is the reverse of removal. If the
thermostatic switch was renewed, refill the
cooling system.5 Radiator, expansion tank
and coolant reservoir-
removal and refitting
3
Warning: Do not start this
procedure until the engine is
completely cool.
Radiator
Removal
1Disconnect the negative battery cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Drain the coolant into a container (see
Chapter 1).
3Remove both the upper and lower radiator
hoses, and the small expansion tank hose from
the top left of the radiator (see illustration).
4Remove the cooling fan and shroud (see
Section 4).
3•4 Cooling, heating and air conditioning systems
4.20 Disconnect the fan’s electrical
connector (large arrow) and remove the
bolts (small arrows) on single-fan models -
grille is removed here
3261 Jaguar XJ6 4.15 Disconnect the electrical connector (A) from the
thermostatic switch (B) in the radiator and bypass it with a
jumper wire (C) - the fan should operate now with the ignition on
4.17 Disconnect the fan wiring connector and connect jumper
wires from there directly to the positive and negative terminals of
the battery - the purple wire’s terminal should receive the battery
power and the black wire’s terminal should be earthed

17A coolant recovery bottle is used on 1988
and 1989 models, located in the passenger’s
inner wing. The plastic inner wing splash
shield must be removed for access to the
recovery bottle (see Chapter 11). Disconnect
the recovery hose and remove the mounting
screws to renew the recovery bottle (see
illustration). Models from 1990 on do not
have the recovery bottle, but do have a larger
expansion tank.
18Refitting of either expansion tank or
recovery bottle is the reverse of removal.
6 Engine oil cooler- renewal
2
1Models from 1988 through 1991 have a
engine oil cooler, mounted ahead of the
radiator. The engine’s mechanical fan draws
air through the oil cooler, cooling off hot
engine oil that is circulated from the engine by
steel tubes. Access to the cooler is with the
grille removed (refer to Chapter 11 for grille
removal).
2To renew the oil cooler, first disconnect thetwo fittings connecting the lines to the cooler
(see illustration).
Caution: The engine should be cool for this
procedure, and you should have a small
drain pan handy because the fittings are
on the bottom of the cooler and will
probably drip some oil on dismantling.
3Remove the mounting nuts to take the
cooler out of the vehicle (see illustration).
4The other ends of the oil cooler tubes
mount to a block just below the oil filter. With
a drain pan handy, remove the nut retaining
both pipes to the block.
5Refitting the oil cooler and oil lines is the
reverse of removal. When refitting the lines to
the block or the cooler, use new O-rings.7 Water pump- check
1
1A failure in the water pump can cause
serious engine damage due to overheating.
2With the engine running and warmed to
normal operating temperature, squeeze the
upper radiator hose. If the water pump is
working properly, a pressure surge should be
felt as the hose is released.
Warning: Keep hands away from
fan blades!
3Water pumps are equipped with weep or
vent holes (see illustration). If a failure occurs
in the pump seal, coolant will leak from this
hole. In most cases it will be necessary to use
a flashlight to find the hole on the water pump
by looking through the space behind the
pulley just below the water pump shaft.
4If the water pump shaft bearings fail there
may be a howling sound at the front of the
engine while it is running. Bearing wear can be
felt if the water pump pulley is rocked up anddown. Do not mistake drivebelt slippage,
which causes a squealing sound, for water
pump failure. Spray automotive drivebelt
dressing on the belts to eliminate the belt as a
possible cause of the noise.
8 Water pump and pipes-
renewal
3
Warning: Do not start this
procedure until the engine is
completely cool.
1Disconnect the negative battery cable and
drain the cooling system (see Chapter 1).
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Refer to Section 4 to remove the
mechanical fan and clutch (if applicable to
your model).
3Refer to Chapter 1 for removal of the
drivebelts.
3•6 Cooling, heating and air conditioning systems
6.3 Remove the mounting nuts (arrowed)
to take the oil cooler out
7.3 Check the weep hole (arrowed) for
signs of leakage (pump removed for
clarity) - grey discolouration is normal,
large brown stains indicates seal failure
3261 Jaguar XJ6 5.17 The recovery bottle (arrowed) on 1988 and 1989 models is
located in the footwell - disconnect the hoses and the two
mounting screws
6.2 Disconnect the two metal oil lines (arrowed) where they
mount to the bottom of the cooler - use two spanners

4Remove the water pump mounting bolts
(see illustration).
Note 1:The water pump is sold as a complete
assembly, including the rear housing with the
hose connections. Unless the rear housing is
corroded or cracked, many Jaguar mechanics
only refit the pump assembly itself, using the
original rear housing with all its hoses intact.
However, if the engine has a great deal of
years or mileage on it, it would be a good idea
to renew those hoses as well, in which case
the new rear housing can be installed.
Note 2:There are three different lengths of
water pump bolts. The longer bolts retain the
pump and rear housing to the engine(see
illustration 7.3).
5If the pump doesn’t come loose right away,
tap it with a soft-faced hammer to break the
gasket seal. Be careful not to hit the radiator
fins with the pump during removal.
6Thoroughly clean all sealing surfaces,
removing all traces of gasket or sealant from
the back of the pump and the face of the
housing.
7Apply a bead of RTV sealant to the sealing
surface on the back of the pump. Refit the
pump and bolts, tightening the bolts to the
torque listed in this Chapter’s Specifications.
8Refit the remaining parts in the reverse
order of removal. Note:If the pump has been
renewed after many miles of usage, it’s a good
idea to also renew the hoses connected to the
water pump housing(see illustrations). Refer
to Chapter 2A for intake manifold removal to
access the coolant pipes and hoses. If you
have noticed water leaks or stains on the left
side of the engine, the leaks may be coming
from these pipes and hoses.
9Refill the cooling system (see Chapter 1),
run the engine and check for leaks and proper
operation.
9 Coolant temperature
sender unit- check and
renewal
2
Warning: Do not start this
procedure until the engine is
completely cool.
Check
1If the coolant temperature gauge is
inoperative, check the fuses first (Chapter 12).
2If the temperature gauge indicates
excessive temperature after running awhile,
see the Fault finding section at the rear of the
manual.
3If the temperature gauge indicates Hot as
soon as the engine is started cold, disconnect
the wire at the coolant temperature sender
(see illustration). If the gauge reading drops,
renew the sender unit. If the reading remains
high, the wire to the gauge may be shorted to
ground, or the gauge is faulty.
4If the coolant temperature gauge fails to
show any indication after the engine has been
warmed up, (approx. 10 minutes) and the
fuses checked out OK, shut off the engine.
Disconnect the wire at the sender unit and,
using a jumper wire, connect the wire to a
clean ground on the engine. Briefly turn on the
ignition without starting the engine. If the
gauge now indicates Hot, renew the sender
unit.
5If the gauge fails to respond, the circuit may
be open or the gauge may be faulty - see
Chapter 12 for additional information.
Renewal
6Drain the coolant (see Chapter 1).
7Disconnect the electrical connector from
the sender unit.8Using a deep socket or a spanner, remove
the sender unit.
9Refit the new unit and tighten it securely.
Do not use thread sealant as it may
electrically insulate the sender unit.
10Reconnect the wiring connector, refill the
cooling system and check for coolant leakage
and proper gauge function.
10 Heating and air conditioning
blower motors- circuit check
and component renewal
3
Warning: Later models are
equipped with airbags. To
prevent accidental deployment
of the airbag, which could cause
personal injury or damage to the airbag
system, DO NOT work in the vicinity of the
steering wheel or instrument panel. Jaguar
recommends that, on airbag-equipped
models, the following procedure should be
left to a dealer service department or other
repair workshop because of the special
tools and techniques required to disable
the airbag system.
1Disconnect the battery negative cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2There are two blower motors, one under the
left side of the dash and one behind the glove
compartment (see illustration). If the blower
doesn’t work, check the fuse and all
connections in the circuit for looseness and
corrosion. Make sure the battery is fully
charged. To access the right blower, remove
the glove compartment liner, the glove
compartment door and the right lower dash
panel (see Chapter 11).
Warning: When working around
the area behind the glove box,
watch out for a strip of sheet
metal bracing that has a very
sharp edge (see illustration). Apply some
heavy duct tape to the edge of the brace
before beginning work in this area, or you
could injure your hands.
Cooling, heating and air conditioning systems 3•7
3
8.4 Remove the water pump mounting
bolts (arrows indicate five visible here)8.8a Once the water pump is removed, the
rear housing (arrowed) is held in place only
by the hoses - check them for leakage and
condition whenever the pump is disturbed8.8b The water pipe (arrowed) may need
new gaskets where it meets the block - the
pipe is best accessed from below or with
the intake manifold unbolted
9.3 The coolant temperature sender unit
(arrowed) is located in the top of the
thermostat housing - it is the sender unit
with the single wire
3261 Jaguar XJ6

11Separate the housing halves and pull up
the plastic plate holding the motor and fan
(see illustration). The fan doesn’t come off
the motor, but loosen the clamp-bolt on the
motor’s mount bracket and slide the motor
and fan out for renewal (see illustration).
Note:Some 1988 models had problems with
cracking of the fan blades and noise from the
blowers. These blowers and fans have been
superseded with improved parts, available
from your Jaguar dealer.
12When either blower housing is separated,
you’ll find two relays mounted inside (see
illustration). These are the blower isolation
relay and blower relay. Before refitting the
blower housing in the car, refer to Chapter 12
for testing of these relays.
13Refitting is the reverse of removal. Check
for proper operation.11 Heater core-
removal and refitting
4
Warning: Later model vehicles
are equipped with airbags. To
prevent the accidental deploy-
ment of the airbag, which could
cause personal injury or damage to the
airbag system, DO NOT work in the vicinity
of the steering wheel or instrument panel.
The manufacturer recommends that, on
airbag-equipped models, the following
procedure should be left to a dealer service
department or other repair workshop
because of the special tools and techniques
required to disable the airbag system.1Disconnect the battery negative cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Drain the cooling system (see Chapter 1).
Disconnect the heater hoses where they enter
the bulkhead (see illustration). Note:Use
compressed air in one of the pipes to blow out
any remaining coolant and collect it. This will
prevent any spills on the carpeting when the
heater core is removed. Plug the pipes to
prevent any remaining coolant from spilling out.
3Refer to Chapter 11 for removal of the
under-dash panels on both the driver and
passenger sides, and removal of the glovebox.
Warning: When working around
the area behind the glove box,
watch out for a strip of sheet
Cooling, heating and air conditioning systems 3•9
3
3261 Jaguar XJ6 10.11a Separate the housing halves - the blower motor (arrowed)
is attached to a plastic plate sandwiched between the
two housing halves
10.11b Loosen the clamp bolt (arrowed) on the motor bracket and
then pull the motor and fan out as an assembly
10.12 Inside the blower case are the blower and isolation relays
(arrowed) - while the case is apart, test these relays for
proper operation11.2 Disconnect the heater hoses from the pipes at the bulkhead
(small arrows) - the large arrow indicates the evaporator case
retaining nut

metal bracing that has a very sharp edge
(see illustration 10.2b). Apply some heavy
duct tape to the edge of the brace before
beginning work in this area, or you could
injure your hands.
4On the passenger’s side, under the dash,
remove the screws holding the plastic cover
where the heater pipes enter the heater/air
conditioning housing (see illustration).
5With the cover off, there is access to
remove the four Allen bolts holding the two
pipes to the heater core (see illustration).
6Move to the right side and unbolt the
climate control computer and pull it down and
away from the heater/air conditioning housing
(see illustrations).
7Remove the four small screws and remove
the plastic plate over the heater core, right
behind where the climate control computer
had been (see illustration).
8Carefully slide the heater core out from the
right side of the heating/air conditioning
housing (see illustration). Note:Keep plenty
of towels or rags on the carpeting to catch any
coolant that may drip.
9Refitting is the reverse order of removal.
When refitting the heater core, make sure all
of the foam insulation strips are in place and
refit new O-rings where the heater pipes enter
the core (see illustration).
10Refill the cooling system, reconnect the
battery and run the engine. Check for leaks
and proper system operation.
12 Heater and air conditioning
control assembly- check,
removal and refitting
4
Warning: Later models are
equipped with airbags. To
prevent the accidental deploy-
ment of the airbag, which could
cause personal injury or damage to the
airbag system, DO NOT work in the vicinity
of the steering wheel or instrument panel.
The manufacturer recommends that, on
airbag-equipped models, the following
procedure should be left to a dealer service
department or other repair workshopbecause of the special tools and
techniques required to disable the airbag
system.
Removal and refitting
1Disconnect the battery negative cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
2Refer to Chapter 11 for removal of the
console heater control/radio assembly trim
bezel.
3Remove the mounting screws retaining the
heater/air conditioning control assembly to
the console (see illustrations). Pull the
assembly out, and disconnect the electrical
connectors.
3•10 Cooling, heating and air conditioning systems
11.4 Remove these screws (small arrows)
to remove the plastic plate over the heater
core pipes on the left side11.5 With the cover off, remove the Allen
bolts (arrows indicate three of the four) to
pull the coolant pipes out of the left side of
the heater core11.6a Remove three screws (one arrowed;
one at the top-back and one below) to take
out the climate-control computer on right
side of heater/air conditioning assembly
11.6b Pull away the climate control
computer (arrowed)11.7 Remove the four screws (arrowed)
and the heater core cover plate11.8 Pull the heater core out to the right
3261 Jaguar XJ6
11.9 Retain the original foam insulation on
the heater core or transfer to the new
core, and replace the two O-rings
(arrowed)
12.3a Remove these six screws (arrowed)
to release the control panel/radio
assembly from the console

repair facility. Always wear eye protection
when working near air conditioning system
fittings.
1Have the refrigerant discharged and
recovered by an air conditioning technician.
2Disconnect the refrigerant lines (see
illustration)from the receiver/drier and cap
the open fittings to prevent entry of moisture.
3Remove the three nuts holding the
receiver/drier to the radiator support and
remove the receiver/drier. Note:On 1993 and
1994 models, the receiver/drier is a long
tubular style mounted to the top-front of the
radiator support. The grille must be removed
for access on these models (see Chapter 11
for grille removal).
4Refitting is the reverse of removal.
5Have the system evacuated, charged and
leak tested by the workshop that discharged
it. If the receiver/drier was renewed, have
them add new refrigeration oil to the
compressor, about 28 cc (one ounce). Use
only the refrigerant oil compatible with the
refrigerant of your system (R-12 or R-134a).
15 Air conditioning
compressor-
removal and refitting
4
Warning: The air conditioning
system is under high pressure.
Do not loosen any hose fittings
or remove any components until
the system has been discharged. Air
conditioning refrigerant should be properly
discharged into an EPA-approved
recovery/recycling unit by a dealer service
department or an automotive air
conditioning repair facility. Always wear
eye protection when disconnecting air
conditioning system fittings.
1Have the refrigerant discharged by an
automotive air conditioning technician.2Disconnect the battery negative cable.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
3Remove the drivebelt from the compressor
(see Chapter 1).
4Detach the electrical connector and
disconnect the flexible refrigerant lines (see
illustration).
5Unbolt the compressor and lift it from the
vehicle (see illustration).
6If a new or rebuilt compressor is being
installed, drain the fluid from the new unit by
opening the drain plug and by tilting the
compressor to the rear so that any remaining
oil will come out the ports in the back normally
covered by the plate and hard lines. Refit the
drain plug and end-plate and add 199 cc
(7 fluid ounces) of new oil of a type compatible
with the type refrigerant in your system.
7Refitting is the reverse of removal. Renew
any O-rings with new ones specifically made
for the type of refrigerant in your system and
lubricate them with refrigerant oil, also
designed specifically for your refrigerant.
8Have the system evacuated, recharged and
tested by the workshop that discharged it.
16 Air conditioning condenser-
removal and refitting
4
Warning: The air conditioning
system is under high pressure.
Do not loosen any hose fittings
or remove any components until
the system has been discharged. Air
conditioning refrigerant should be properly
discharged into an EPA-approved
recovery/recycling unit by a dealer service
department or an automotive air con-
ditioning repair facility. Always wear eye
protection when disconnecting air
conditioning system fittings.
1Have the refrigerant discharged and
recovered by an air conditioning technician.
2Remove the radiator cowl panel as
described in Section 5.
3Using two spanners to avoid twisting the
fittings, disconnect the inlet and outlet lines
from the condenser (see illustration).
4Pull the condenser straight up and out of
the vehicle.
5Refitting is the reverse of removal. When
refitting the condenser, be sure the rubber
Cooling, heating and air conditioning systems 3•13
3
15.5 Remove the lower mounting bolts
and the adjuster bolt (arrowed)16.3 Disconnect the two lines, then pull up
on the condenser (arrowed)
3261 Jaguar XJ6 14.2 After the system has been discharged, unbolt the two
refrigerant lines (left arrows) from the top of the receiver/drier and
cap them - use two spanners when loosening or tightening these
lines - right arrows indicate the two top mounting bolts
15.4 Disconnect the electrical connector (small arrow) at the
compressor, then disconnect the bolt (large arrow) at the
retaining plate that holds the two hoses in place

special electrical device that provides circuit
protection by switching off the ignition and
fuel pump upon impact in the event of vehicle
collision. Later Jaguar models are equipped
with an additional specialised inertia switch.
This later device switches OFF all ignition fed
circuits, locks the fuel filler cap, locks the boot
(only if doors are locked) and unlocks the
doors if they are locked during the accident.
All these functions are directed by the inertia
switch. The inertia switch is located behind
the left kick panel. Refer to Chapter 12 for
more information.
Exhaust system
The exhaust system includes an exhaust
manifold equipped with an exhaust oxygen
sensor, a catalytic converter, an exhaust pipe,
and a silencer.
The catalytic converter is an emission
control device added to the exhaust system to
reduce pollutants. A single-bed converter is
used in combination with a three-way
(reduction) catalyst. See Chapter 6 for more
information regarding the catalytic converter.
2 Fuel pressure relief
1
Warning: Petrol is extremely
flammable, so take extra
precautions when you work on
any part of the fuel system.
Don’t smoke or allow open flames or bare
light bulbs near the work area, and don’t
work in a garage where a natural gas-type
appliance (such as a water heater or a
clothes dryer) with a pilot light is present.
Since petrol is carcinogenic, wear latex
gloves when there’s a possibility of being
exposed to fuel, and, if you spill any fuel on
your skin, rinse it off immediately with soap
and water. Mop up any spills immediately
and do not store fuel-soaked rags wherethey could ignite. The fuel system is under
constant pressure, so, if any fuel lines are
to be disconnected, the fuel pressure in
the system must be relieved first. When
you perform any kind of work on the fuel
system, wear safety glasses and have a
Class B type fire extinguisher on hand.
1Before servicing any fuel system
component, you must relieve the fuel pressure
to minimise the risk of fire or personal injury.
2Remove the fuel filler cap - this will relieve
any pressure built up in the tank.
3Remove the fuel pump relay from the main
relay panel (see illustrations). Note:These
models are equipped with a fuel pump relay
that is located in various areas of the vehicle
depending on the year. On 1988 and 1989
models, the fuel pump relay is under the
glovebox. On 1990 to 1992 models, the fuel
pump relay is in the engine compartment on
the left side, attached to the brake pedal
hanger. On 1993 models, the fuel pump relay
is in the boot. On 1994 models, it’s in the
engine compartment on the right side of the
bulkhead. Refer to the relay location charts in
Chapter 12 for additional information.
4Start the engine and wait for the engine to
stall, then turn the ignition key to Off.
Disconnect the cable from the negativeterminal of the battery before beginning any
work on the fuel system.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
5The fuel system is now depressurised.
Note:Place a rag around the fuel line before
removing any hose clamp or fitting to prevent
any residual fuel from spilling onto the engine.
3 Fuel pump/fuel pressure-
check
2
Warning: Petrol is extremely
flammable, so take extra
precautions when you work on
any part of the fuel system. See
the Warning in Section 2.
Note: To perform the fuel pressure test, you
will need to obtain a fuel pressure gauge and
adapter set (fuel line fittings).
Note: On 1988 to 1990 models, the fuel pump
may chatter excessively and the engine may
stall frequently during hot weather. If stalling
occurs, the engine will restart after a cool-
down period. Dual fuel pumps can be installed
by a dealer service department or other
qualified repair facility to remedy this problem.
Preliminary inspection
1Should the fuel system fail to deliver the
proper amount of fuel, or any fuel at all,
inspect it as follows. Remove the fuel filler
cap. Have an assistant turn the ignition key to
the ON position (engine not running) while you
listen at the fuel filler opening. You should
hear a whirring sound that lasts for a couple of
seconds. On 1988 to 1990 models, listen
behind the left rear wheel (external fuel pump)
for the fuel pump sound.
2If you don’t hear anything, check the fuel
pump relay (see illustration 2.3a, b or c)and
4•2 Fuel and exhaust systems
2.3c On 1992 models, the fuel pump relay
is located in the left rear corner of the
engine compartment
3261 Jaguar XJ6 2.3a Relay locations on a 1988 model
2.3b Relay locations on a 1989 model

circuit. If all circuits are intact and not
damaged, check the inertia switch. Note: The
inertia switch is a special device that shuts
down power to the ignition and the fuel pump
in the event of an accident. See Chapter 12 for
checking and resetting procedures for the
inertia switch.
3Remove the relay and check for battery
voltage to the fuel pump relay connector (see
illustration). If there is battery voltage
present, check the relay for proper operation.
Refer to the relay checking procedure in
Chapter 12. Note:If battery voltage is not
available, check for battery voltage to the main
relay(see illustration). Refer to the relay
location diagrams in Chapter 12. The main
relay, which is located next to the fuel pump
relay, supplies voltage to the fuel pump and
ignition system.
4If battery voltage is present, check for
battery voltage directly at the fuel pump
electrical connector (see illustrations), within
two seconds of the ignition key being turned
On. If there is no voltage, check the fuel pump
circuit. If there is voltage present, renew the
pump (see Section 4). Note:It will be
necessary to raise the vehicle and support it
securely on axle stands to gain access to the
fuel pump electrical connectors. Have an
assistant operate the ignition key and be sure
to block the front wheels to avoid any
movement of the vehicle.
Operating pressure check
5Relieve the fuel system pressure (see
Section 2). Detach the cable from the negative
battery terminal.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
6Detach the fuel line from the fuel rail and
connect a fuel pressure gauge(see
illustrations)between the fuel pulsationdamper and the fuel rail. Tighten the hose
clamps securely.
7Attach the cable to the negative battery
terminal. Start the engine.
8Note the fuel pressure and compare it with
the pressure listed in this Chapter’s
Specifications.
9Disconnect the vacuum hose from the fuelpressure regulator and hook up a hand-held
vacuum pump (see illustration)to the port on
the fuel pressure regulator.
10Read the fuel pressure gauge with vacuum
applied to the pressure regulator and also with
no vacuum applied. The fuel pressure should
decrease as vacuum increases (and increase
as vacuum decreases).
Fuel and exhaust systems 4•3
4
3261 Jaguar XJ6 3.3a Checking for battery voltage at the fuel pump relay
connector ( 1989 model)
3.3b Checking for battery voltage to the main relay (1989 model)
3.6a Remove the fuel line from the fuel
pulsation damper . . .
3.4b Check for battery voltage to the
fuel pump on the harness connector near
the fuel tank on models with in-tank
fuel pumps3.4a Remove the rubber boot from the fuel
pump electrical connector and check for
voltage while an assistant turns the
ignition key (1989 model shown)
3.6b . . . then refit the fuel pressure gauge
between the fuel rail and the fuel pressure
damper using a T-fitting

11Reconnect the vacuum hose to the
regulator and check the fuel pressure at idle,
comparing your reading with the value listed
in this Chapter’s Specifications. Disconnect
the vacuum hose and watch the gauge - the
pressure should jump up considerably as
soon as the hose is disconnected. If it
doesn’t, check for a vacuum signal to the fuel
pressure regulator (see Step 14).
12If the fuel pressure is low, pinch the fuel
return line shut (see illustration)and watch
the gauge. If the pressure doesn’t rise, the
fuel pump is defective or there is a restriction
or leak in the fuel feed line, or the pump is
faulty. If the pressure rises sharply, renew the
pressure regulator.
13If the fuel pressure is too high, turn the
engine off. Disconnect the fuel return line and
blow through it to check for a blockage. If
there is no blockage, renew the fuel pressure
regulator.
14Connect a vacuum gauge to the pressure
regulator vacuum hose. Start the engine and
check for vacuum (see illustration). The fuel
pressure regulator receives manifold vacuum
that decreases (increases fuel pressure) when
the engine speed is raised (acceleration). If
there isn’t vacuum present, check for a
clogged hose or vacuum port. If the amount ofvacuum is adequate but the pressure is too
high, renew the fuel pressure regulator.
15Turn the ignition switch to OFF, wait five
minutes and recheck the pressure on the
gauge. Compare the reading with the
specified hold pressure. If the hold pressure is
less than specified:
a) The fuel lines may be leaking.
b) The fuel pressure regulator may be
allowing the fuel pressure to bleed
through to the return line.
c) A fuel injector (or injectors) may be
leaking.
d) The fuel pump may be defective.
4 Fuel pump-
removal and refitting
3
Warning: Petrol is extremely
flammable, so take extra
precautions when you work on
any part of the fuel system. See
the Warning in Section 2.
Note 1:On early models (1988 to 1990), an
electric fuel pump is attached to the chassis
next to the fuel tank. On later models (1991 to
1994), the fuel pump is inside the fuel tank.
Note 2: On 1988 to 1990 models, the fuel
pump may chatter excessively and the engine
may stall frequently during hot weather. If
stalling occurs, the engine will restart after a
cool-down period. Dual fuel pumps can be
installed by a dealer service department or
other qualified repair facility to remedy this
problem.
1Remove the fuel tank filler cap to relieve
any pressure in the fuel tank. Relieve the fuel
pressure (see Section 2).
2Disconnect the cable from the negative
terminal of the battery.
Caution: If the stereo in your vehicle is
equipped with an anti-theft system, make
sure you have the correct activation code
before disconnecting the battery.
External fuel pumps
3Raise the vehicle and support it securely on
axle stands.
4Disconnect the fuel lines from the fuel pump.
5Disconnect the electrical connectors from
the fuel pump (see illustration 3.4a).
6Remove the fuel pump bracket retaining
nuts (see illustration).
7Carefully withdraw the fuel pump from the
rubber case inside the fuel pump bracket and
angle the fuel pump over the rear suspension
and out near the wheel on the left side of the
vehicle.
8Refitting is the reverse of removal.
In-tank fuel pumps
9Raise the vehicle and support it securely on
axle stands.
10Disconnect the fuel pump and fuel level
sender unit electrical connectors and the fuel
lines.
11Remove the fuel tank from the boot (see
Section 7).
12Disconnect the fuel lines from the evap-
orative flange (see illustration). Remove the
lock ring with a hammer and brass punch,
tapping the lock ring anti-clockwise.
13Withdraw the fuel pump module from the
fuel tank. Note: The fuel pump module is
4•4 Fuel and exhaust systems
3.14 Connect a vacuum gauge to the
vacuum line leading to the fuel pressure
regulator and check the vacuum source4.6 Remove the fuel pump mounting nuts
(arrowed) and slide the fuel pump out of
the rubber casing (1989 model shown)
3261 Jaguar XJ6 3.9 Check fuel pressure without vacuum applied to the fuel
pressure regulator, then with vacuum applied; fuel pressure
should DECREASE as vacuum INCREASES
3.12 Using a pair of pliers, squeeze the return line and observe
the fuel pressure increase (wrap a rag around the fuel line so you
don’t damage it)