fuel line JAGUAR XJ6 1997 2.G Workshop Manual

These models are equipped with dual overhead cam in-line six-
cylinder engines. The engines feature a computer-controlled ignition
system and electronic fuel injection. Transmissions are a four-speed
automatic equipped with a lock-up torque converter. The transmission
is mounted to the back of the engine, and power is transmitted to the
fully independent rear axle through a two-piece propshaft. The
differential is bolted solidly to a frame crossmember and drives the
wheels through driveshafts equipped with inner and outer U-joints.
The front suspension is fitted with upper and lower control arms, coil
springs and shock absorbers. The rear suspension is an independent
type suspension which also have coil spring/shock absorber
assemblies and a lower control arm. The rear driveshaft acts as the
upper control arm.
Power-assisted Anti-lock Brake Systems (ABS) with four-wheel disc
brakes are standard equipment on all Jaguar XJ6 models covered in
this manual. Power rack-and-pinion steering is also standard
equipment.
Your Jaguar manual
The aim of this manual is to help you get the best value from your
vehicle. It can do so in several ways. It can help you decide what work
must be done (even should you choose to get it done by a garage). It
will also provide information on routine maintenance and servicing, and
give a logical course of action and diagnosis when random faults
occur. However, it is hoped that you will use the manual by tackling the
work yourself. On simpler jobs it may even be quicker than booking the
car into a garage and going there twice, to leave and collect it. Perhaps
most important, a lot of money can be saved by avoiding the costs a
garage must charge to cover its labour and overheads.
The manual has drawings and descriptions to show the function of
the various components so that their layout can be understood. Tasks
are described and photographed in a clear step-by-step sequence.
Notes for UK readers
Because this manual was originally written in the US, its layout
differs from our UK-originated manuals. The preliminary and reference
sections have been re-written specifically for the UK market, and the
maintenance schedule has been amended to suit UK vehicles.
However, it will be noticed that some references to componentsremain in the US style; the UK equivalent of US components and
various other US words is given in the Section headed “Use of
English”. It should be remembered that the project vehicle used in the
main Chapters of this manual was a left-hand drive US model;
therefore, the position of the steering wheel, steering column and
pedals, etc. will be on the opposite side of the vehicle on UK models.
References to “right” and “left” will need to be considered carefully to
decide which applies to UK models (eg the headlight dipped beams
should be adjusted to dip to the left of the headlight vertical line
described in Chapter 12, instead of to the right on US models). In other
instances, no reference is made to the location of a particular item, but
that item may be located on the opposite side of the vehicle on UK
models. Reference to the underbonnet photos at the start of Chapter 1
will give the reader the location of the engine compartment
components on UK models.
All specifications in the main Chapters of the manual appear in
Imperial form; the equivalent metric values can be calculated using the
“Conversion factors”page.
The only other major difference between UK and US models is in the
level of emission control equipment fitted to the vehicle. To meet the
strict emission standards present in the US, all vehicles for that market
are fitted with various emission control systems (see Chapter 6), most
of which are not fitted to the corresponding UK model, especially so on
early models. Therefore, a lot of the information contained in Chapter 6
is not applicable to UK models.
Acknowledgements
Thanks are due to Jean Preis, Rich Wilson and Ray Marcuse of
Silver Star Jaguar (Thousand Oaks, CA), Rick Calaci of Conejo Imports
(Newbury Park, CA) and Jim Strohmeier and Jonathan Lund of British
Motor Cars (Thousand Oaks, CA), for providing valuable technical
information. Technical writers who contributed to this project include
Jeff Kibler, Robert Maddox and Jay Storer.
We take great pride in the accuracy of information given in this
manual, but vehicle manufacturers make alterations and design
changes during the production run of a particular vehicle of which
they do not inform us. No liability can be accepted by the authors
or publishers for loss, damage or injury caused by any errors in, or
omissions from, the information given.
0•4Introduction
3261 Jaguar XJ6
Haynes mechanic, author and photographer with 1989 Jaguar XJ6

silencer and catalytic converter. If the
components can come in contact with the
body or suspension parts, secure the exhaust
system with new mounts.
5Check the running condition of the engine
by inspecting inside the end of the tailpipe.
The exhaust deposits here are an indication of
engine state-of-tune. If the pipe is black and
sooty or coated with white deposits, the
engine is in need of a tune-up, including a
thorough fuel system inspection.
11 Braking system - general
check and adjustment
2
Warning: The dust created by
the brake system may contain
asbestos, which is harmful to
your health. Never blow it out
with compressed air and don’t inhale any
of it. An approved filtering mask should be
worn when working on the brakes. Do not,
under any circumstances, use petroleum-
based solvents to clean brake parts. Use
brake system cleaner only! Try to use non-
asbestos replacement parts whenever
possible.
Note: For detailed photographs of the brake
system, refer to Chapter 9.
1In addition to the specified intervals, the
brakes should be inspected every time the
wheels are removed or whenever a defect is
suspected. Any of the following symptoms
could indicate a potential brake system
defect: The vehicle pulls to one side when the
brake pedal is depressed; the brakes make
squealing or dragging noises when applied;
brake pedal travel is excessive; the pedal
pulsates; brake fluid leaks, usually onto the
inside of the tyre or wheel.
2The disc brakes have built-in electrical wear
indicators which cause a warning lamp to
illuminate on the instrument panel when
they’re worn to the renewal point. When the
warning light comes on, replace the pads
immediately or expensive damage to the
discs can result.
3Loosen the wheel nuts.
4Raise the vehicle and place it securely on
axle stands.
5Remove the wheels.
Disc brakes
6There are two pads (an outer and an inner)
in each caliper. The pads are visible through
inspection holes in each caliper (see Haynes
Hint).
7Check the pad thickness by looking at each
end of the caliper and through the inspection
hole in the caliper body. If the lining material is
less than the thickness listed in this Chapter’s
Specifications, replace the pads. Note:Keep
in mind that the lining material is riveted or
bonded to a metal backing plate and the metal
portion is not included in this measurement.8If it is difficult to determine the exact
thickness of the remaining pad material by the
above method, or if you are at all concerned
about the condition of the pads, remove the
caliper(s), then remove the pads from the
calipers for further inspection (see Chapter 9).
9Once the pads are removed from the
calipers, clean them with brake cleaner and
re-measure them with a ruler or a vernier
caliper.
10Measure the disc thickness with a
micrometer to make sure that it still has
service life remaining. If any disc is thinner
than the specified minimum thickness,
replace it (refer to Chapter 9). Even if the disc
has service life remaining, check its condition.
Look for scoring, gouging and burned spots. If
these conditions exist, remove the disc and
have it resurfaced (see Chapter 9).
11Before refitting the wheels, check all
brake lines and hoses for damage, wear,
deformation, cracks, corrosion, leakage,
bends and twists, particularly in the vicinity of
the rubber hoses at the calipers (see
illustration). Check the clamps for tightness
and the connections for leakage. Make sure
that all hoses and lines are clear of sharp
edges, moving parts and the exhaust system.
If any of the above conditions are noted,
repair, reroute or replace the lines and/or
fittings as necessary (see Chapter 9).
Hydraulic brake servo check
12Sit in the driver’s seat and perform the
following sequence of tests.
13Start the engine, run it for about a minute
and turn it off. Then firmly depress the brake
several times - the pedal travel should
decrease with each application.
14With the brake fully depressed, start the
engine - the pedal should move down a little
when the engine starts.
15Depress the brake, stop the engine and
hold the pedal in for about 30 seconds - the
pedal should neither sink nor rise.
16If your brakes do not operate as
described above when the preceding tests
are performed, the brake servo is either in
need of repair or has failed. Refer to Chapter 9
for the removal procedure.
Handbrake
17Slowly pull up on the handbrake and
count the number of clicks you hear until the
handle is up as far as it will go. The
adjustment should be within the specified
number of clicks listed in this Chapter’s
Specifications. If you hear more or fewer
clicks, it’s time to adjust the handbrake (refer
to Chapter 9).
18An alternative method of checking the
handbrake is to park the vehicle on a steep hill
with the handbrake set and the transmission
in Neutral (be sure to stay in the vehicle during
this check!). If the handbrake cannot prevent
the vehicle from rolling, it is in need of
adjustment (see Chapter 9). Whenever a fault
is suspected, the brake discs should be
removed and the handbrake assemblies
themselves should be visually inspected.
12 Steering
and suspension check
2
Note: The steering linkage and suspension
components should be checked periodically.
Worn or damaged suspension and steering
linkage components can result in excessive
and abnormal tyre wear, poor ride quality and
vehicle handling and reduced fuel economy.
For detailed illustrations of the steering and
suspension components, refer to Chapter 10.
With the wheels on the ground
1Park the vehicle on level ground, turn the
engine off and set the handbrake. Check the
tyre pressures and check that the wheel nuts
are tightened to the specified torque.
2Push down at one corner of the vehicle,
then release it while noting the movement of
the body. It should stop moving and come to
rest in a level position with one or two
bounces. When bouncing the vehicle up and
down, listen for squeaks and noises from the
suspension components.
3If the vehicle continues to move up-and-
down or if it fails to return to its original
1•12Every 7500 miles or 6 months
11.11 Check along the brake hoses
and at each fitting (arrowed) for
deterioration and cracks
3261 Jaguar XJ6
You will find an inspection hole like this
in each caliper - placing a ruler across
the hole should enable you to determine
the thickness of remaining pad material
for both inner and outer pads

16 Spark plug renewal
2
Refer to Section 4, renewing the plugs
regardless of their apparent condition.
17 Air cleaner element renewal
1
1The air filter is located inside a housing at
the left side of the engine compartment. To
remove the air filter, release the four spring
clips that secure the two halves of the air
cleaner housing together, then lift the cover
up and remove the air filter element (see
illustration).
Caution: Never drive the car with the air
cleaner removed. Excessive engine wear
could result and backfiring could even
cause a fire under the bonnet.
2Wipe out the inside of the air cleaner
housing.
3Place the new filter into the air cleaner
housing, making sure it seats properly.
4Refitting the cover is the reverse of removal.
18 Fuel filter renewal
2
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-typeappliance (such as a water heater or
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 where
they 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 (see
Chapter 4 for more information). When you
perform any kind of work on the fuel
system, wear safety glasses and have a
Class B type fire extinguisher on hand.
1The canister type filter is mounted
underneath the car on the passenger’s side
frame rail just in front of the left rear tyre.
2Depressurise the fuel system (refer to
Chapter 4), then disconnect the cable from
the negative terminal of the battery.
3On 1988 to 1990 models, detach the banjo
bolt from the outlet side of the filter then
remove the union from the inlet side of the
filter. Unscrew the filter mounting bolt and
remove the filter (see illustration).
4On 1991 to 1994 models, the fuel filter has
quick-disconnect fittings that do not require 8Clean and lubricate the handbrake cable,
along with the cable guides and levers. This
can be done by smearing some of the chassis
grease onto the cable and its related parts
with your fingers.
9Open the bonnet and smear a little chassis
grease on the bonnet latch mechanism. Have
an assistant pull the bonnet release lever from
inside the car as you lubricate the cable at the
latch.
10Lubricate all the hinges (door, bonnet,
etc.) with engine oil to keep them in proper
working order.
11The key lock cylinders can be lubricated
with spray graphite or silicone lubricant, which
is available at motor factors.12Lubricate the door weather-stripping with
silicone spray. This will reduce chafing and
retard wear.
15 Road test
1
Instruments and electrical
equipment
1Check the operation of all instruments and
electrical equipment.
2Make sure that all instruments read
correctly, and switch on all electrical
equipment in turn, to check that it functions
properly.
Steering and suspension
3Check for any abnormalities in the steering,
suspension, handling or road “feel”.
4Drive the car, and check that there are no
unusual vibrations or noises.
5Check that the steering feels positive, with
no excessive “sloppiness”, or roughness, and
check for any suspension noises when
cornering and driving over bumps.
Drivetrain
6Check the performance of the engine and
transmission, listening for any unusual noises.7Make sure that the engine runs smoothly
when idling, and that there is no hesitation
when accelerating.
8Check that the gear changing action of the
transmission is smooth and progressive and
that the drive is taken up smoothly from a
standing start.
Braking system
9Make sure that the car does not pull to one
side when braking, and that the wheels do not
lock prematurely when braking hard.
10Check that there is no vibration through
the steering when braking.
11Check that the handbrake operates
correctly without excessive movement of the
lever, and that it holds the car stationary on a
slope.
12Test the operation of the brake servo unit
as follows. With the engine off, depress the
footbrake four or five times to exhaust the
vacuum. Hold the brake pedal depressed, then
start the engine. As the engine starts, there
should be a noticeable “give” in the brake
pedal as vacuum builds up. Allow the engine to
run for at least two minutes, and then switch it
off. If the brake pedal is depressed now, it
should be possible to detect a hiss from the
servo as the pedal is depressed. After about
four or five depressions, no further hissing
should be heard, and the pedal should feel
considerably harder.
1•14Every 7500 miles or 6 months
17.1 Detach the clips and separate the
cover, then slide the filter element out of
the housing
3261 Jaguar XJ6
14.6 Grease fittings for the rear
driveshafts are located in the centre
on each U-joint
Every 15 000 miles (24 000 km) or 12 months

hand tools to remove. Simply slide back the
locking collars and remove the inlet and outlet
fuel lines (see illustration). Detach the filter
mounting bracket and discard the old filter in
a proper container.
5Note the direction of the arrow on the
outside of the filter; it should be pointed
towards the front of the car. Make sure the
new filter is installed so that it’s facing the
proper direction. Note:Always refit new
copper washers where equipped.
6Refit the inlet and outlet fittings then tighten
the filter mounting bracket. Reconnect the
battery cable, start the engine and check for
leaks.
19 Ignition system check
2
1The spark plug leads should be checked
whenever new spark plugs are installed.
2Begin this procedure by making a visual
check of the spark plug leads while the engine
is running. In a darkened garage (make sure
there is adequate ventilation) start the engine
and observe each plug lead. Be careful not to
come into contact with any moving engine
parts. If there is a break in the lead, you will
see arcing or a small spark at the damaged
area. If arcing is noticed, make a note to
obtain new leads, then allow the engine to
cool and check the distributor cap and rotor.
3The spark plug leads should be inspected
one at a time to prevent mixing up the order,
which is essential for proper engine operation.
Each original plug lead should be numbered
to help identify its location. If the number is
illegible, a piece of tape can be marked with
the correct number and wrapped around the
plug lead.
4Disconnect the plug lead from the spark
plug. A removal tool can be used for this
purpose or you can grasp the rubber boot,
twist the boot half a turn and pull the boot
free. Do not pull on the lead itself.
5Check inside the boot for corrosion, which
will look like a white crusty powder.6Push the lead and boot back onto the end
of the spark plug. It should fit tightly onto the
end of the plug. If it doesn’t, remove the lead
and use pliers to carefully crimp the metal
connector inside the lead boot until the fit is
snug.
7Using a clean rag, wipe the entire length of
the lead to remove built-up dirt and grease.
Once the lead is clean, check for burns,
cracks and other damage. Do not bend the
lead sharply, because the conductor might
break.
8Disconnect the spark plug lead from the
distributor cap. Again, pull only on the rubber
boot. Check for corrosion and a tight fit.
Reinsert the lead in the distributor cap.
9Inspect the remaining spark plug leads,
making sure that each one is securely
fastened at the distributor and spark plug
when the check is complete.10If new spark plug leads are required,
purchase a set for your specific engine model.
Remove and replace the leads one at a time
to avoid mix-ups in the firing order.
11Detach the distributor cap by unsnapping
the cap retaining clips. Look inside it for
cracks, carbon tracks and worn, burned or
loose contacts (see illustrations).
12Pull the rotor off the distributor shaft and
examine it for cracks and carbon tracks (see
illustrations). Replace the cap and rotor if any
damage or defects are noted.
13It is common practice to refit a new cap
and rotor whenever new spark plug leads are
installed. When refitting a new cap, remove
the leads from the old cap one at a time and
attach them to the new cap in the exact same
location Note:If an accidental mix-up occurs,
refer to the firing order Specifications at the
beginning of this Chapter.
Every 15 000 miles or 12 months 1•15
1
19.11a Unsnap the distributor cap
retaining clips - pull the cap up and away
to access the rotor
19.11b Shown here are some of the
common defects to look for when
inspecting the distributor cap (typical cap
shown). If in doubt about its condition,
fit a new one
19.12a Pull off the rotor (arrowed) and
inspect it thoroughly
19.12b Check the ignition rotor for wear
and corrosion as indicated here (if in doubt
about its condition, buy a new one)
3261 Jaguar XJ6 18.3 Remove the banjo bolt from the
outlet side (B), detach the fitting from the
inlet side (A) and unscrew the filter
mounting bolt (C)
18.4 On 1991 to 1994 models, slide back
the locking collars and remove the inlet
and outlet fuel lines

Torque wrench settings*Nm lbf ft
Camshaft bearing cap bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Camshaft sprocket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft damper-to-crankshaft bolt
3.2 and 3.6 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 151
4.0 litre . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 to 220 133 to 162
Crankshaft pulley to damper bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft rear oil seal retainer bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Crankshaft sensor bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Cylinder head bolts
Step 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 44
Step 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tighten an additional 90° (1/4 turn)
Driveplate bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 to 149 91 to 110
Engine mounts
To engine block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 to 66 36 to 39
To chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 to 24 16 to 18
Exhaust manifold heat shield fasteners . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Exhaust manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Intake manifold nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Oil pump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Sump bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Sump bolts, adapter to pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 to 54 36 to 40
Timing chain cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 27 16 to 20
Valve cover screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 to 12 7 to 9
*Note:Refer to Part B for additional specifications
2A•2 Engine in-car repair procedures
3261 Jaguar XJ6
1 General information
This Part of Chapter 2 is devoted to in-car
repair procedures for the in-line six-cylinder
engines. All information concerning engine
removal and refitting and engine block and
cylinder head overhaul can be found in Part B
of this Chapter.
The following repair procedures are based
on the assumption that the engine is installed
in the car. If the engine has been removed
from the car and mounted on a stand, many of
the steps outlined in this Part of Chapter 2 will
not apply. We have photographed some in-
car engine procedures with the engine on a
stand for photographic purposes.
The Specifications included in this Part of
Chapter 2 apply only to the procedures
contained in this Part. Part B of Chapter 2
includes the Specifications necessary for
cylinder head and engine block rebuilding.
2 Repair operations possible
with the engine in the car
Many repair operations can be
accomplished without removing the engine
from the car.
Clean the engine compartment and the
exterior of the engine with some type of
degreaser before any work is done. It will
make the job easier and help keep dirt out of
the internal areas of the engine.
Depending on the components involved, itmay be helpful to remove the bonnet to
improve access to the engine as repairs are
performed (refer to Chapter 11 if necessary).
Cover the wings to prevent damage to the
paint. Special pads are available, but an old
bedspread or blanket will also work.
If vacuum, exhaust, oil or coolant leaks
develop, indicating a need for gasket or seal
renewal, the repairs can generally be made
with the engine in the car. The intake and
exhaust manifold gaskets, crankshaft oil seals
and cylinder head gasket are all accessible
with the engine in place (although rear oil seal
renewal involves removal of the transmission).
The sump is difficult for a home mechanic to
replace without a hoist and other specialised
equipment, since the front suspension,
steering and crossmember must be lowered
to allow enough clearance for sump removal.
If such equipment is not available, the
alternative would be to remove the engine for
renewal of the sump or oil pump. Note:We
assume that the home mechanic does not
have access to the specialised equipment,
and have photographed our subject engine
out of the car for some procedures.
Exterior engine components, such as the
intake and exhaust manifolds, the water
pump, the starter motor, the alternator, the
distributor and the fuel system components
can be removed for repair with the engine in
place.
Since the cylinder head can be removed
with the engine in-car, camshaft and valve
component servicing can also be
accomplished. Renewal of the timing chains
and sprockets is also possible with the engine
in-car.
3 Top Dead Centre (TDC) for
number one piston- locating
1
Note:The following procedure is based on the
assumption that the distributor is correctly
installed. If you are trying to locate TDC to refit
the distributor correctly, piston position must
be determined by feeling for compression at
the number one spark plug hole, then aligning
the ignition timing marks (see paragraph 8).
1Top Dead Centre (TDC) is the highest point
in the cylinder that each piston reaches as it
travels up the cylinder bore. Each piston
reaches TDC on the compression stroke and
again on the exhaust stroke, but TDC
generally refers to piston position on the
compression stroke.
2Positioning the piston(s) at TDC is an
essential part of many procedures such as
camshaft and timing chain/sprocket removal
and distributor removal.
3Before beginning this procedure, be sure to
place the transmission in Neutral and apply
the handbrake or block the rear wheels. Also,
disable the ignition system by detaching the
coil wire from the centre terminal of the
distributor cap and grounding it on the engine
block with a jumper wire. Remove the spark
plugs (see Chapter 1).
4In order to bring any piston to TDC, the
crankshaft must be turned using one of the
methods outlined below. When looking at the
timing chain end of the engine, normal
crankshaft rotation is clockwise.
a) The preferred method is to turn the
crankshaft with a socket and ratchet

8Tighten the screws to the torque listed in
this Chapter’s Specifications in three or four
equal steps.
9Refit the remaining components, start the
engine and check for oil leaks.
5 Intake manifold-
removal and refitting
2
Removal
1Disconnect the negative cable from 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.
2Refer to Chapter 4 to remove the
accelerator and cruise-control linkage, safely
relieve the fuel system pressure, and
disconnect the fuel supply lines.
3Label or mark and detach the PCV and
vacuum hoses connected to the intake
manifold, (see illustration).
4The intake manifold can be removed with
the injectors and fuel rail still in place.
Disconnect the electrical connectors at
each injector (label them first for reassembly).
If the injectors are to be removed from the
intake manifold, refer to Chapter 4.
5Refer to Chapter 4 and remove the throttle
body.6Remove the three nuts retaining the oil filler
tube bracket, then pull the tube up as far as
possible (see illustrations).
7Remove the ground strap and intake
manifold mounting nuts/bolts, then detach the
intake manifold from the engine (see
illustrations).
Refitting
8Clean the mating surfaces of the intake
manifold and the cylinder head mounting
surface with lacquer thinner or acetone. If the
gasket shows signs of leaking, have the
manifold checked for warpage at an
automotive machine workshop and
resurfaced if necessary.
9Refit a new gasket, then position the intake
manifold on the cylinder head and refit the
nuts/bolts (see illustration).
10Tighten the nuts/bolts in three or four
equal steps to the torque listed in this
Chapter’s Specifications. Work from the
centre out towards the ends to avoid warping
the manifold.
11Refit the remaining parts in the reverse
order of removal.
12Before starting the engine, check the
throttle linkage for smooth operation.
13Run the engine and check for coolant and
vacuum leaks.
14Road test the car and check for proper
operation of all accessories, including the
cruise control system.
6 Exhaust manifolds-
removal and refitting
2
Warning: The engine must be
completely cool before beginning
this procedure.
Removal
1Disconnect the negative cable from 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.
2On 1990 and later models, disconnect the
EGR pipe and remove the EGR valve from the
top of the exhaust manifold (see Chapter 6).
3Apply penetrating oil to the exhaust
manifold mounting nuts/bolts, and the nuts
retaining the exhaust pipes to the manifolds.
After the nuts have soaked, remove the nuts
retaining the exhaust pipes to the manifolds
and the lower bolt from the heat shield (see
illustration).
4Remove the heat shield from the exhaust
manifolds(see illustration).
5Disconnect the electrical connector to the
oxygen sensor. Unless the oxygen sensor is
being renewed, leave the sensor in place.
6Remove the nuts/bolts and detach the
manifolds and gaskets (see illustration).
2A•4 Engine in-car repair procedures
5.3 The various hoses should be marked
to ensure correct refitting5.6a Remove the oil filler tube bracket
nuts (arrowed) . . .5.6b . . . pull the tube up to dislodge it
from the housing - it won’t come out, but
can be removed with the intake manifold
5.7a Remove the ground strap from the
front stud (arrowed), and the engine wiring
harness clips from the other studs5.7b Remove the intake manifold bolts/
nuts and remove the intake manifold - the
upper fasteners are studs/nuts, while the
lower row are bolts (two arrowed)5.9 Refit the new intake manifold gasket
over the studs (arrowed) refit the manifold
3261 Jaguar XJ6

rebuilt engine or short block, some rebuilders
will not warranty their engines unless the
radiator has been professionally flushed. Also,
we don’t recommend overhauling the oil
pump - always refit a new one when an engine
is rebuilt.
Before beginning the engine overhaul, read
through the entire procedure to familiarise
yourself with the scope and requirements of
the job. Overhauling an engine isn’t difficult,
but it is time-consuming. Plan on the vehicle
being tied up for a minimum of two weeks,
especially if parts must be taken to an
automotive machine workshop for repair or
reconditioning. Check on availability of parts
and make sure that any necessary special
tools and equipment are obtained in advance.
Most work can be done with typical hand
tools, although a number of precision
measuring tools are required for inspecting
parts to determine if they must be renewed.
Often an automotive machine workshop will
handle the inspection of parts and offer
advice concerning reconditioning and
renewal. Note:Always wait until the engine
has been completely dismantled and all
components, especially the engine block,
have been inspected before deciding what
service and repair operations must be
performed by an automotive machine
workshop. Since the engine block’s condition
will be the major factor to consider when
determining whether to overhaul the original
engine or buy a rebuilt one, never purchase
parts or have machine work done on other
components until the engine block has been
thoroughly inspected. As a general rule, time
is the primary cost of an overhaul, so it
doesn’t pay to refit worn or substandard
parts.
If it turns out that a number of major
components are beyond reconditioning, it
may be cost effective to buy a factory-rebuilt
engine from a Jaguar dealership.
As a final note, to ensure maximum life and
minimum trouble from a rebuilt engine,
everything must be assembled with care in a
spotlessly-clean environment.
3 Vacuum gauge
diagnostic checks
2
A vacuum gauge provides valuable
information about what is going on in the
engine at a low cost. You can check for worn
rings or cylinder walls, leaking cylinder head or
intake manifold gaskets, incorrect carburettor
adjustments, restricted exhaust, stuck or
burned valves, weak valve springs, improper
ignition or valve timing and ignition problems.
Unfortunately, vacuum gauge readings are
easy to misinterpret, so they should be used
with other tests to confirm the diagnosis.
Both the absolute readings and the rate of
needle movement are important for accurate
interpretation. Most gauges measure vacuumin inches of mercury (in-Hg). As vacuum
increases (or atmospheric pressure decreases),
the reading will decrease. Also, for every
1000 foot increase in elevation above sea level;
the gauge readings will decrease about one
inch of mercury.
Connect the vacuum gauge directly to
intake manifold vacuum, not to ported (above
the throttle plate) vacuum (see illustration).
Be sure no hoses are left disconnected during
the test or false readings will result.
Before you begin the test, allow the engine
to warm up completely. Block the wheels and
set the handbrake. With the transmission in
Park, start the engine and allow it to run at
normal idle speed.
Warning: Carefully inspect the
fan blades for cracks or damage
before starting the engine. Keep
your hands and the vacuum
tester clear of the fan and do not stand in
front of the vehicle or in line with the fan
when the engine is running.
Read the vacuum gauge; an average,
healthy engine should normally produce
between 17 and 22 inches of vacuum with a
fairly steady needle.
Refer to the following vacuum gauge
readings and what they indicate about the
engines condition:
1A low steady reading usually indicates a
leaking gasket between the intake manifold
and carburettor or throttle body, a leaky
vacuum hose, late ignition timing or incorrect
camshaft timing. Check ignition timing with a
timing light and eliminate all other possible
causes, utilising the tests provided in this
Chapter before you remove the timing belt
cover to check the timing marks.
2If the reading is three to eight inches below
normal and it fluctuates at that low reading,
suspect an intake manifold gasket leak at an
intake port or a faulty injector.
3If the needle has regular drops of about two
to four inches at a steady rate the valves are
probably leaking. Perform a compression or
leak-down test to confirm this.
4An irregular drop or down-flick of the
needle can be caused by a sticking valve or
an ignition misfire. Perform a compression or
leak-down test and read the spark plugs.5A rapid vibration of about four in-Hg
vibration at idle combined with exhaust
smoke indicates worn valve guides. Perform a
leak-down test to confirm this. If the rapid
vibration occurs with an increase in engine
speed, check for a leaking intake manifold
gasket or cylinder head gasket, weak valve
springs, burned valves or ignition misfire.
6A slight fluctuation, say one inch up and
down, may mean ignition problems. Check all
the usual tune-up items and, if necessary, run
the engine on an ignition analyser.
7If there is a large fluctuation, perform a
compression or leak-down test to look for a
weak or dead cylinder or a blown cylinder
head gasket.
8If the needle moves slowly through a wide
range, check for a clogged PCV system,
incorrect idle fuel mixture, throttle body or
intake manifold gasket leaks.
9Check for a slow return after revving the
engine by quickly snapping the throttle open
until the engine reaches about 2,500 rpm and
let it shut. Normally the reading should drop to
near zero, rise above normal idle reading
(about 5 in.-Hg over) and then return to the
previous idle reading. If the vacuum returns
slowly and doesn’t peak when the throttle is
snapped shut, the rings may be worn. If there
is a long delay, look for a restricted exhaust
system (often the silencer or catalytic
converter). An easy way to check this is to
temporarily disconnect the exhaust ahead of
the suspected part and redo the test.
4 Cylinder compression check
2
1A compression check will tell you what
mechanical condition the upper end (pistons,
rings, valves, cylinder head gasket) of your
engine is in. Specifically, it can tell you if the
compression is down due to leakage caused
by worn piston rings, defective valves and
seats or a blown cylinder head gasket. Note:
The engine must be at normal operating
temperature and the battery must be fully
charged for this check.
2Begin by cleaning the area around the
spark plugs before you remove them
(compressed air should be used, if available,
otherwise a small brush or even a bicycle tyre
pump will work). The idea is to prevent dirt
from getting into the cylinders as the
compression check is being done.
3Remove all of the spark plugs from the
engine (see Chapter 1).
4Block the throttle wide open.
5Detach the coil wire from the centre of the
distributor cap and ground it on the engine
block. Use a jumper wire with alligator clips on
each end to ensure a good earth. Also,
remove the fuel pump relay (see Chapter 4) to
disable the fuel pump during the compression
test.
Engine removal and overhaul procedures 2B•3
2B
3.4 The vacuum gauge is easily attached
to a port on the intake manifold, and can
tell a lot about an engine’s state of tune
3261 Jaguar XJ6

6Refit the compression gauge in the spark
plug hole (see illustration).
7Crank the engine over at least seven
compression strokes and watch the gauge.
The compression should build up quickly in a
healthy engine. Low compression on the first
stroke, followed by gradually increasing
pressure on successive strokes, indicates
worn piston rings. A low compression reading
on the first stroke, which doesn’t build up
during successive strokes, indicates leaking
valves or a blown cylinder head gasket (a
cracked cylinder head could also be the
cause). Deposits on the undersides of the
valve heads can also cause low compression.
Record the highest gauge reading obtained.
8Repeat the procedure for the remaining
cylinders and compare the results to this
Chapter’s Specifications.
9Add some engine oil (about three squirts
from a plunger-type oil can) to each cylinder,
through the spark plug hole, and repeat the
test.
10If the compression increases after the oil
is added, the piston rings are definitely worn.
If the compression doesn’t increase
significantly, the leakage is occurring at the
valves or cylinder head gasket. Leakage past
the valves may be caused by burned valve
seats and/or faces or warped, cracked or bent
valves.
11If two adjacent cylinders have equally low
compression, there’s a strong possibility that
the cylinder head gasket between them is
blown. The appearance of coolant in the
combustion chambers or the crankcase
would verify this condition.
12If one cylinder is 20 percent lower than the
others, and the engine has a slightly rough
idle, a worn exhaust lobe on the camshaft
could be the cause.
13If the compression is unusually high, the
combustion chambers are probably coated
with carbon deposits. If that’s the case, the
cylinder head(s) should be removed and
decarbonised.
14If compression is way down or varies
greatly between cylinders, it would be a goodidea to have a leak-down test performed by
an automotive repair workshop. This test will
pinpoint exactly where the leakage is
occurring and how severe it is.
5 Engine removal-
methods and precautions
If you’ve decided that an engine must be
removed for overhaul or major repair work,
several preliminary steps should be taken.
Locating a suitable place to work is
extremely important. Adequate work space,
along with storage space for the vehicle, will
be needed. If a workshop or garage isn’t
available, at the very least a flat, level, clean
work surface made of concrete or asphalt is
required.
Cleaning the engine compartment and
engine before beginning the removal
procedure will help keep tools clean and
organised.
An engine hoist or A-frame will also be
necessary. Make sure the equipment is rated
in excess of the combined weight of the
engine and transmission. Safety is of primary
importance, considering the potential hazards
involved in lifting the engine out of the vehicle.
If the engine is being removed by a novice,
a helper should be available. Advice and aid
from someone more experienced would also
be helpful. There are many instances when
one person cannot simultaneously perform all
of the operations required when lifting the
engine out of the vehicle.
Plan the operation ahead of time. Arrange
for or obtain all of the tools and equipment
you’ll need prior to beginning the job. Some of
the equipment necessary to perform engine
removal and refitting safely and with relative
ease are (in addition to an engine hoist) a
heavy duty trolley jack, complete sets of
spanners and sockets as described in the
front of this manual, wooden blocks and
plenty of rags and cleaning solvent for
mopping up spilled oil, coolant and petrol. If
the hoist must be rented, make sure that you
arrange for it in advance and perform all of the
operations possible without it beforehand.
This will save you money and time.
Plan for the vehicle to be out of use for
quite a while. A machine workshop will be
required to perform some of the work which
the do-it-yourselfer can’t accomplish without
special equipment. These shops often have a
busy schedule, so it would be a good idea to
consult them before removing the engine in
order to accurately estimate the amount of
time required to rebuild or repair components
that may need work.
Always be extremely careful when removing
and refitting the engine. Serious injury can
result from careless actions. Plan ahead, take
your time and a job of this nature, although
major, can be accomplished successfully.
6 Engine- removal and refitting
3
Note:Read through the entire Section before
beginning this procedure. It is recommended
to remove the engine and transmission from
the top as a unit, then separate the engine
from the transmission on the workshop floor. If
the transmission is not being serviced, it is
possible to leave the transmission in the
vehicle and remove the engine from the top by
itself, by removing the crankshaft damper and
tilting up the front end of the engine for
clearance,but access to the upper
bellhousing bolts is only practical when the
rear transmission mount and driveshaft have
been removed and the transmission is angled
down with a trolley jack.
Removal
1Relieve the fuel system pressure (see
Chapter 4).
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.
3Place protective covers on the wings and
cowl and remove the bonnet (see Chapter 11).
4Remove the battery and battery tray.
5Remove the air cleaner assembly (see
Chapter 4).
6Raise the vehicle and support it securely on
axle stands. Drain the cooling system and
engine oil and remove the drivebelts (see
Chapter 1).
7Clearly label, then disconnect all vacuum
lines, coolant and emissions hoses, wiring
harness connectors and earth straps.
Masking tape and/or a touch up paint
applicator work well for marking items (see
illustration). Take instant photos or sketch
the locations of components and brackets.
8Remove the cooling fan(s) and radiator (see
Chapter 3).
9Disconnect the heater hoses.
10Release the residual fuel pressure in the
tank by removing the petrol cap, then detach
the fuel lines connecting the engine to the
chassis (see Chapter 4). Plug or cap all open
fittings.
2B•4 Engine removal and overhaul procedures
4.6 A compression gauge with a threaded
fitting for the spark plug hole is preferred
over the type that requires hand pressure
to maintain the seal - be sure to block
open the throttle valve as far as possible
during the compression check!
6.7 Label both ends of each wire and hose
before disconnecting it
3261 Jaguar XJ6

5If equipped with an automatic transmission,
disconnect the cooler lines from the radiator
(see illustrations). Disconnect the cooling fan
switch connector (see illustration 4.15).
Place a drip pan to catch the fluid and cap the
fittings. Note:The transmission oil cooler lines
enter the radiator on the left, while the power
steering cooler lines attach on the right side of
the radiator. On 1993 and 1994 models, the
cooler fittings require a spring-lock coupling
tool, normally used on fuel lines or air
conditioning lines.
6Remove the four bolts from the radiator
cowl panel and take off the panel (see
illustration).
7Lift out the radiator. Be aware of dripping
fluids and the sharp fins. Take care not to
damage the radiator fins by contact with other
parts.
8With the radiator removed, it can be
inspected for leaks, damage and internal
blockage. If repairs are necessary, have a
radiator specialist or dealer service department
perform the work, as special techniques are
required. Check the rubber mounting pads on
the bottom of the radiator (see illustration). If
they’re cracked or damaged, get new ones
before refitting the radiator.
9Bugs and dirt can be cleaned from the
radiator with compressed air and a soft brush.
Don’t bend the cooling fins as this is done.
Warning: Wear eye protection.
Refitting
10Refitting is the reverse of the removal
procedure. Be sure the rubber mounts are in
place on the bottom of the radiator.
11After refitting, fill the cooling system with
the proper mixture of antifreeze and water.
Refer to Chapter 1 if necessary.
12Start the engine and check for leaks.
Allow the engine to reach normal operating
temperature, indicated by both radiator hoses
becoming hot. Recheck the coolant level and
add more if required.
13On automatic transmission equipped
models, check and add fluid as needed and
check the power steering fluid level as well.
Expansion tank and coolant
reservoir, removal and refitting
14The expansion tank is located at the top
of the left-hand side inner wing. With the
cooling system drained below the level of the
expansion tank, remove the hoses, the
coolant level probe and the two screws
mounting it to the body (see illustration).
15Wash out and inspect the reservoir for
cracks and chafing. Renew it if damaged.16If the low-coolant level light has been
showing on the instrument panel, even when
the coolant level is correct, disconnect the
sensor’s connector and test it with an
ohmmeter (see illustration). The sensor
should be renewed if the resistance at the
connections is over 150 ohms.
Caution: Using a long-necked funnel to
add coolant can damage the sensor, which
is just below the expansion tank filler neck.
Cooling, heating and air conditioning systems 3•5
3
5.5a At the left side of the radiator,
disconnect the automatic transmission
cooler lines (small arrows) and the lower
radiator hose (larger arrow)5.5b Disconnect the power steering cooler
lines (small arrows) at the right side of the
radiator, and the upper radiator hose
(large arrow)
3261 Jaguar XJ6 5.3 Remove the clamp and the hose going
to the expansion tank
5.6 Remove the bolts (arrowed) and take
off the radiator cowl panel
5.14 The expansion tank is located on the
left inner wing
A Hose to recovery tank (where applicable)
B Hose to radiator
C Hose to thermostat housing
D Hose to water pump housing
E Mounting screws
F Low-coolant-level sensor
5.8 There are rubber mounts (arrowed)
for the radiator and the condenser -
they must be in place when these
components are reinstalled
5.16 The low-coolant-level sensor can be
tested with an ohmmeter - resistance
should be below 150 ohms - gently use a
pair of long-neck pliers to move the sensor
up and down in the tank to get a reading

3261 Jaguar XJ6
4
Chapter 4
Fuel and exhaust systems
Fuel system
Fuel pressure:kPa psi
Ignition ON, engine not running . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 to 300 38 to 44
Engine idling:
Vacuum hose detached from fuel pressure regulator . . . . . . . . . . . 280 to 320 40 to 46
Vacuum hose attached to fuel pressure regulator . . . . . . . . . . . . . 210 to 260 30 to 38
Fuel system hold pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 21
Fuel injector resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.0 to 3.0 ohms
Idle speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Must be set by authorised service department
Torque wrench settingsNm lbf ft
Throttle body mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 14
Fuel rail mounting bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 9 Accelerator cable - removal, refitting and adjustment . . . . . . . . . . . 10
Air cleaner assembly - removal and refitting . . . . . . . . . . . . . . . . . . . 9
Catalytic converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 6
CHECK ENGINE light . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 6
Electronic Fuel Injection (EFI) system - check . . . . . . . . . . . . . . . . . . 12
Electronic Fuel Injection (EFI) system - component check
and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Electronic Fuel Injection (EFI) system - general information . . . . . . . 11
Exhaust manifold - removal and refitting . . . . . . . . . . . See Chapter 2A
Exhaust system check . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Exhaust system servicing - general information . . . . . . . . . . . . . . . . 14
Fuel filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1Fuel level sender unit - check and renewal . . . . . . . . . . . . . . . . . . . . 5
Fuel lines and fittings - inspection and renewal . . . . . . . . . . . . . . . . 6
Fuel pressure relief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Fuel pump - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Fuel pump/fuel pressure - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Fuel system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Fuel tank - removal and refitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Fuel tank cap gasket renewal . . . . . . . . . . . . . . . . . . . . . See Chapter 1
Fuel tank cleaning and repair - general information . . . . . . . . . . . . . 8
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Intake manifold - removal and refitting . . . . . . . . . . . . See Chapter 2A
Underbonnet hose check and renewal . . . . . . . . . . . . . . See Chapter 1
4•1
Specifications Contents
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321
1 General information
The fuel system consists of a fuel tank, an
electric fuel pump either located externally,
next to the fuel tank (1988 to 1990 models) or
in the fuel tank (1991 to 1994 models), an EFI
fuel pump relay and main relay, an inertia
switch, fuel injectors and fuel rail, an air
cleaner assembly and a throttle body unit.
Multi Point Fuel Injection (MPFI)
system
Multi point fuel injection uses timed
impulses to sequentially inject the fuel directly
into the intake port of each cylinder. Theinjectors are controlled by the Electronic
Control Unit (ECU). The ECU monitors various
engine parameters and delivers the exact
amount of fuel, in the correct sequence, into
the intake ports. The throttle body serves only
to control the amount of air passing into the
system. Because each cylinder is equipped
with an injector mounted immediately
adjacent to the intake valve, much better
control of the fuel/air mixture ratio is possible.
Fuel pump and lines
Fuel is circulated from the fuel tank to the
fuel injection system, and back to the fuel
tank, through a pair of metal lines running
along the underside of the vehicle. On early
models (1988 to 1990), an electric fuel pump
is attached to the chassis next to the fueltank. On later models (1991 to 1994), the fuel
pump and fuel level sender unit are located
inside the fuel tank. A vapour return system
routes all vapours and hot fuel back to the fuel
tank through a separate return line.
The fuel pump will operate as long as the
engine is cranking or running and the ECU is
receiving ignition reference pulses from the
electronic ignition system (see Chapter 5). If
there are no reference pulses, the fuel pump
will shut off after 2 or 3 seconds.Inertia switch
These models are equipped with an inertia
switch that is wired in the circuit between the
fuel pump relay, the ignition switch and the
fuel pump (refer to the wiring diagrams at the
end of Chapter 12). The inertia switch is a