1997 JAGUAR XJ6 check engine

3261 Jaguar XJ6
Weekly checks0•15
Battery
Caution:Before carrying out any work on the
vehicle battery, read the precautions given in
"Safety first" at the start of this manual.
4Make sure that the battery tray is in good
condition, and that the clamp is tight.
Corrosion on the tray, retaining clamp and the
battery itself can be removed with a solution
of water and baking soda. Thoroughly rinse all
cleaned areas with water. Any metal parts
damaged by corrosion should be covered
with a zinc-based primer, then painted.
4Periodically (approximately every three
months), check the charge condition of the
battery as described in Chapter 5.
4If the battery is flat, and you need to jump
start your vehicle, see Roadside Repairs.
The battery is located in the left-hand,
rear corner of the engine compartment.
Check the battery terminals for signs of
corrosion and examine the battery leads
closely for signs of damage.1Check the battery lead clamps for
tightness to ensure good electrical
connections.2
Battery corrosion can be kept to a
minimum by applying a layer of
petroleum jelly to the clamps and
terminals after they are reconnected.If corrosion (white, fluffy deposits) is
evident, remove the cables from the
battery terminals, clean them with a small
wire brush, then refit them. Automotive stores
sell a tool for cleaning the battery post . . .3. . . as well as the battery cable clamps4
Bulbs and fuses
4Check all external lights and the horn. Refer
to the appropriate Sections of Chapter 12 for
details if any of the circuits are found to be
inoperative.4Visually check all accessible wiring
connectors, harnesses and retaining clips for
security, and for signs of chafing or damage.
If you need to check your
brake lights and indicators
unaided, back up to a wall or
garage door and operate the
lights. The reflected light should show if
they are working properly.
If a single indicator light, stop light or
headlight has failed, it is likely that a bulb
has blown and will need to be replaced.
Refer to Chapter 12 for details. If both stop
lights have failed, it is possible that the switch
has failed (see Chapter 9).If more than one indicator light or tail light
has failed it is likely that either a fuse has
blown or that there is a fault in the circuit.
The fuseboxes are located behind the left and
right side kick panels and in the centre
console glove box (see Chapter 12).
2
To replace a blown fuse, simply pull it out
and fit a new fuse of the correct rating
(see Chapter 12). If the fuse blows again,
it is important that you find out why - a
complete checking procedure is given in
Chapter 12.31

0•16Lubricants, fluids and tyre pressures
3261 Jaguar XJ6
Lubricants and fluids
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . Multigrade engine oil to API SG or higher (Duckhams QS, QXR, Hypergrade Plus,
Hypergrade, or 10W-40 Motor Oil)
Cooling system . . . . . . . . . . . . . . . . . . . Ethylene glycol based (phosphate free) antifreeze
(Duckhams Antifreeze and Summer Coolant)
Automatic transmission . . . . . . . . . . . . Dexron type II automatic transmission fluid (ATF) (Duckhams Uni-Matic)
Differential:
Standard differential . . . . . . . . . . . . . . SAE EP90 to API GL5 (Duckhams 80W-90S Gear Oil)
Powr-lok differential . . . . . . . . . . . . . . . SAE 90 to API GL5 (Duckhams Hypoid 90 DL)
Braking system . . . . . . . . . . . . . . . . . . . Hydraulic fluid to DOT 4 (Duckhams Universal Brake and Clutch Fluid)
Power steering (with separate reservoir) .dependent on year of manufacture and system fitted - refer to your Jaguar dealer
Power hydraulic system . . . . . . . . . . . . . Castrol or Jaguar hydraulic system mineral oil (HSMO) Refer to your Jaguar dealer
Tyre pressures
Note:Tyre pressures must always be checked with the tyres cold to ensure accuracy.
Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 psi (2.3 bar)
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 psi (2.3 bar)
Note:Jaguar state that the tyre pressures maybe reduced by up to 8 psi (0.6 bar) on the front tyres and 6 psi (0.4 bar) on the rear
tyres to increase the ride comfort. This is only allowable if the vehicle is not to be driven at speeds in excess of 100 mph (160 kmh);
if speeds are to exceed this, the tyres must be run at the specified pressures.
Oils perform vital tasks in all engines. The
higher the engine’s performance, the greater
the demand on lubricants to minimise wear as
well as optimise power and economy.
Duckhams tailors lubricants to the highest
technical standards, meeting and exceeding
the demands of all modern engines.
HOW ENGINE OIL WORKS
• Beating friction
Without oil, the surfaces inside your engine
which rub together will heat, fuse and quickly
cause engine seizure. Oil, and its special
additives, forms a molecular barrier between
moving parts, to stop wear and minimise heat
build-up.
• Cooling hot spots
Oil cools parts that the engine’s water-based
coolant cannot reach, bathing the combustion
chamber and pistons, where temperatures
may exceed 1000°C. The oil assists intransferring the heat to the engine cooling
system. Heat in the oil is also lost by air flow
over the sump, and via any auxiliary oil cooler.
• Cleaning the inner engine
Oil washes away combustion by-products
(mainly carbon) on pistons and cylinders,
transporting them to the oil filter, and holding
the smallest particles in suspension until they
are flushed out by an oil change. Duckhams
oils undergo extensive tests in the laboratory,
and on the road.
Engine oil types
Mineral oilsare the “traditional” oils,
generally suited to older engines and cars not
used in harsh conditions. Duckhams
Hypergrade Plus and Hypergradeare well
suited for use in most popular family cars.
Diesel oilssuch as Duckhams Dieselare
specially formulated for Diesel engines,
including turbocharged models and 4x4s.
Synthetic oilsare the state-of-the-art in
lubricants, offering ultimate protection, but at
a fairly high price. One such is Duckhams QS,
for use in ultra-high performance engines.
Semi-synthetic oilsoffer high performance
engine protection, but at less cost than full
synthetic oils. Duckhams QXRis an ideal choice
for hot hatches and hard-driven cars.
For help with technical
queries on lubricants,
call Duckhams Oils
on 0181 290 8207
Choosing your engine oil
Note: It is
antisocial and
illegal to dump oil
down the drain.
To find the
location of your
local oil recycling
bank, call this
number free.

3261 Jaguar XJ6
1
Chapter 1
Routine maintenance and servicing
Air cleaner element renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Automatic transmission fluid and filter renewal . . . . . . . . . . . . . . . . . 26
Automatic transmission fluid level check . . . . . . . . . . . . . . . . . . . . . 8
Battery check and general information . . . . . . . . . . . . . . . . . . . . . . . 6
Brake fluid renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Braking system - general check and adjustment . . . . . . . . . . . . . . . 11
Coolant renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Crankcase ventilation system check . . . . . . . . . . . . . . . . . . . . . . . . . 20
Differential oil level check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Differential oil renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Drivebelt check and renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Engine oil and filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Exhaust system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Front wheel alignment check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Front wheel bearing check and adjustment . . . . . . . . . . . . . . . . . . . 22Fuel filter renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Handbrake shoes check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Headlight beam check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Hose and fluid leak check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Ignition system check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Intensive maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Power hydraulic system fluid level check . . . . . . . . . . . . . . . . . . . . . 5
Propshaft check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Road test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Seat belt check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Spark plug check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Spark plug renewal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Steering and suspension check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1•1
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

Lubricants and fluids
Refer to “Weekly checks”
Capacities
Engine oil
Including oil filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0 litres
Cooling system
All models (approximate):
From dry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.8 litres
Drain and refill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.2 litres
Transmission
Automatic transmission (approximate):
From dry:
3.2 litre model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.4 litres
3.6 and 4.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.0 litres
Drain and refill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 litres
Differential
All models (approximate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 litres
Cooling system
Antifreeze mixture:
50% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection down to -37°C (5°F)
55% antifreeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection down to -45°C (-22°F)
Note:Refer to antifreeze manufacturer for latest recommendations.
Ignition system
Spark plugs:
Type:
3.2 litre model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RC12YCC
3.6 and 4.0 litre models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RC9YCC
Electrode gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9 mm
*The spark plug gap quoted is that recommended by Champion
for their specified plug listed above. If spark plugs of any other type
are to be fitted, refer to their manufacturer’s recommendations.
Engine firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5-3-6-2-4
Distributor rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clockwise
Ignition timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Chapter 5
Brakes
Disc brake pad friction material minimum thickness:
Front . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.0 mm
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.0 mm
Handbrake shoe friction material minimum thickness . . . . . . . . . . . . . . 1.5 mm
Handbrake adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 to 5 clicks
Torque wrench settingsNm lbf ft
Automatic transmission sump pan bolts . . . . . . . . . . . . . . . . . . . . . . . . 8 6
Automatic transmission dipstick tube nut . . . . . . . . . . . . . . . . . . . . . . . 20 15
Spark plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 to 28 17 to 21
Wheel nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102 75
1•2Servicing specifications
3261 Jaguar XJ6
Cylinder location and distributor rotation

The maintenance intervals in this manual are provided with the
assumption that you, not the dealer, will be carrying out the work.
These are the minimum maintenance intervals recommended by us for
vehicles driven daily. If you wish to keep your vehicle in peak condition
at all times, you may wish to perform some of these procedures moreoften. We encourage frequent maintenance, because it enhances the
efficiency, performance and resale value of your vehicle.
When the vehicle is new, it should be serviced by a factory-
authorised dealer service department, in order to preserve the factory
warranty.
Maintenance schedule 1•3
1
3261 Jaguar XJ6
Weekly, or every 250 miles (400 km)
m mCarry out all the operations given in “Weekly
checks”at the start of this manual.
m
mRenew the fuel filter (Section 18)
m mCheck the ignition system components (Section 19)
m mCheck the crankcase ventilation system
(Section 20)
m mCheck the condition and tension of the drivebelt(s)
(Section 21)
m mCheck the front wheel bearing adjustment and
repack with grease (Section 22)
m mCheck the propshaft fasteners are tightened to the
specified torque (Section 23)
m mCheck the front wheel alignment (Section 24)
m mCheck the headlight beam alignment (Section 25)
Every 7500 miles (12 000 km)
or 6 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the engine oil and filter (Section 3)
m mCheck the spark plugs (Section 4)
m mCheck the power hydraulics fluid level (Section 5)
m mCheck the battery (Section 6)
m mCheck all pipes and hoses for signs of damage or
leakage (Section 7)
m mCheck the automatic transmission fluid level
(Section 8)
m mCheck the differential oil level (Section 9)
m mCheck the condition of the exhaust system
(Section 10)
m mCheck the brake pads and discs for wear and
adjust the handbrake (Section 11)
m mCheck the steering and suspension components
for wear or damage and check the wheel nuts are
tightened to the correct torque (Section 12)
m mCheck the condition of the seat belts (Section 13)
m mLubricate all locks and hinges, and exposed cables
(Section 14)
m mCarry out a road test (Section 15)
Every 2 years, regardless of mileage
m
mRenew the coolant (Section 30)
Every 60 000 miles (96 000 km)
In addition to the operations listed previously, carry out the following:
m
mCheck the handbrake shoes for wear (Section 29)
Every 30 000 miles (48 000 km)
or 2 years, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the automatic transmission fluid and filter
(Section 26)
m mRenew the differential oil (Section 27)
m mRenew the brake fluid (Section 28)
Every 15 000 miles (24 000 km)
or 12 months, whichever comes first
In addition to the operations listed previously, carry out the following:
m mRenew the spark plugs (Section 16)
m mRenew the air cleaner element (Section 17)

1 General information
1This Chapter is designed to help the home
mechanic maintain his/her vehicle for safety,
economy, long life and peak performance.
2The Chapter contains a master
maintenance schedule, followed by Sections
dealing specifically with each task in the
schedule. Visual checks, adjustments,
component renewal and other helpful items
are included. Refer to the accompanying
illustrations of the engine compartment and
the underside of the vehicle for the locations
of the various components.
3Servicing your vehicle in accordance with
the mileage/time maintenance schedule and
the following Sections will provide a planned
maintenance programme, which should result
in a long and reliable service life. This is a
comprehensive plan, so maintaining some
items but not others at the specified service
intervals, will not produce the same results.
4As you service your vehicle, you will
discover that many of the procedures can -
and should - be grouped together, because of
the particular procedure being performed, or
because of the proximity of two otherwise-
unrelated components to one another. For
example, if the vehicle is raised for any
reason, the exhaust can be inspected at the
same time as the suspension and steering
components.
5The first step in this maintenance
programme is to prepare yourself before the
actual work begins. Read through all theSections relevant to the work to be carried out,
then make a list and gather all the parts and
tools required. If a problem is encountered,
seek advice from a parts specialist, or a dealer
service department.
2 Intensive maintenance
1If, from the time the vehicle is new, the
routine maintenance schedule is followed
closely, and frequent checks are made of fluid
levels and high-wear items, as suggested
throughout this manual, the engine will be
kept in relatively good running condition, and
the need for additional work will be minimised.
2It is possible that there will be times when
the engine is running poorly due to the lack of
regular maintenance. This is even more likely
if a used vehicle, which has not received
regular and frequent maintenance checks, is
purchased. In such cases, additional work
may need to be carried out, outside of the
regular maintenance intervals.
3If engine wear is suspected, a compression
test (refer to Chapter 2) will provide valuable
information regarding the overall performance
of the main internal components. Such a test
can be used as a basis to decide on the extent
of the work to be carried out. If, for example, a
compression test indicates serious internal
engine wear, conventional maintenance as
described in this Chapter will not greatly
improve the performance of the engine, and
may prove a waste of time and money, unless
extensive overhaul work is carried out first.4The following series of operations are those
which are most often required to improve the
performance of a generally poor-running
engine:
Primary operations
a) Clean, inspect and test the battery
(Section 6).
b) Check all the engine-related fluids (refer
to “Weekly checks”).
c) Check the condition and tension of the
auxiliary drivebelt (Section 21).
d) Renew the spark plugs (Section 16).
e) Inspect the distributor cap and rotor arm
(Section 19).
f) Check the condition of the air filter, and
renew if necessary (Section 17).
g) Renew the fuel filter (Section 18).
h) Check the condition of all hoses, and
check for fluid leaks (Section 7).
i) Check the exhaust gas emissions (see
Chapter 6).
5If the above operations do not prove fully
effective, carry out the following secondary
operations:
Secondary operations
All items listed under “Primary operations”,
plus the following:
a) Check the charging system (refer to
Chapter 5).
b) Check the ignition system (refer to
Chapter 5).
c) Check the fuel system (refer to Chapter 4).
d) Renew the distributor cap and rotor arm
(Section 19).
e) Renew the ignition HT leads (Section 19).
1•6Maintenance procedures
3261 Jaguar XJ6
Every 7500 miles (12 000 km) or 6 months
3 Engine oil and filter renewal
2
1Frequent oil changes are the best
preventive maintenance the home mechanic
can give the engine, because ageing oil
becomes diluted and contaminated, which
leads to premature engine wear.
2Make sure that you have all the necessary
tools before you begin this procedure (see
illustration). You should also have plenty of
rags or newspapers handy for mopping up
any spills.
3Access to the underside of the vehicle is
greatly improved if the vehicle can be lifted on
a hoist, driven onto ramps or supported by
axle stands.
4If this is your first oil change, get under the
vehicle and familiarise yourself with the
location of the oil drain plug. The engine and
3.2 These tools are required when
changing the engine oil and filter
1 Drain pan - It should be fairly shallow in
depth, but wide in order to prevent spills
2 Rubber gloves - When removing the drain
plug and filter, it is inevitable that you will
get oil on your hands (the gloves will
prevent burns)
3 Breaker bar - Sometimes the oil drain plug
is pretty tight and a long breaker bar is
needed to loosen it
4 Socket – To be used with the breaker bar
or a ratchet (must be the correct size to fit
the drain plug)
5 Filter wrench - This is a metal band-type
wrench, which requires clearance around
the filter to be effective
6 Filter wrench - This type fits on the bottom
of the filter and can be turned with a
ratchet or breaker bar (different size
spanners are available for different types of
filters)

exhaust components will be warm during the
actual work, so try to anticipate any potential
problems before the engine and accessories
are hot.
5Park the vehicle on a level spot. Start the
engine and allow it to reach its normal
operating temperature (the needle on the
temperature gauge should be at least above
the bottom mark). Warm oil and contaminates
will flow out more easily. Turn off the engine
when it’s warmed up. Remove the oil filler cap
located next to the valve cover.
6Raise the vehicle and support it on axle
stands.
Warning: To avoid personal
injury, never get beneath the
vehicle when it is supported by
only by a jack. The jack provided
with your vehicle is designed solely for
raising the vehicle to remove and replace
the wheels. Always use axle stands to
support the vehicle when it becomes
necessary to place your body underneath
the vehicle.
7Being careful not to touch the hot exhaust
components, place the drain pan under the
drain plug in the bottom of the pan and
remove the plug (see illustration). You may
want to wear gloves while unscrewing the
plug the final few turns if the engine is really
hot.
8Allow the old oil to drain into the pan. It may
be necessary to move the pan farther under
the engine as the oil flow slows to a trickle.
Inspect the old oil for the presence of metal
shavings and chips.
9After all the oil has drained, wipe off the
drain plug with a clean rag. Even minute metal
particles clinging to the plug would
immediately contaminate the new oil.
10Clean the area around the drain plug
opening, refit the plug and tighten it securely,
but do not strip the threads.
11Move the drain pan into position under the
oil filter.
12Remove all tools, rags, etc. from under
the vehicle, being careful not to spill the oil in
the drain pan, then lower the vehicle.
13Loosen the oil filter (see illustration)by
turning it anti-clockwise with the filter wrench.
Any standard filter wrench should work. Oncethe filter is loose, use your hands to unscrew
it from the block. Just as the filter comes
away from the block, immediately tilt the open
end up to prevent the oil inside the filter from
spilling out.
Warning: The engine exhaust
pipes may still be hot, so be
careful.
14With a clean rag, wipe off the mounting
surface on the block. If a residue of old oil is
allowed to remain, it will smoke when the
block is heated up. It will also prevent the new
filter from seating properly. Also make sure
that the none of the old gasket remains stuck
to the mounting surface. It can be removed
with a scraper if necessary.
15Compare the old filter with the new one to
make sure they are the same type. Smear
some engine oil on the rubber gasket of the
new filter and screw it into place (see
illustration). Because over-tightening the
filter will damage the gasket, do not use
a filter wrench to tighten the filter. Tighten it by
hand until the gasket contacts the seating
surface. Then seat the filter by giving it an
additional 3/4-turn.
16Add new oil to the engine through the oil
filler cap next to the valve cover. Use a spout
or funnel to prevent oil from spilling onto the
top of the engine. Pour three litres of fresh oil
into the engine. Wait a few minutes to allow
the oil to drain into the pan, then check the
level on the oil dipstick (see “Weekly checks”).
If the oil level is at or near the H mark, refit the
filler cap hand tight, start the engine and allow
the new oil to circulate.
17Allow the engine to run for about a minute.
While the engine is running, look under the
vehicle and check for leaks at the sump drain
plug and around the oil filter. If either isleaking, stop the engine and tighten the plug
or filter slightly.
18Wait a few minutes to allow the oil to
trickle down into the pan, then recheck the
level on the dipstick and, if necessary, add
enough oil to bring the level to the H mark.
19During the first few trips after an oil
change, make it a point to check frequently
for leaks and proper oil level.
20The old oil drained from the engine cannot
be reused in its present state and should be
disposed of. Check with your local authority,
or with a local garage to see whether they will
accept the oil for recycling. Don’tpour used
oil into drains or onto the ground. After the oil
has cooled, it can be drained into a suitable
container (capped plastic jugs, topped
bottles, etc.) for transport to an approved
disposal site.
4 Spark plug check
2
1Spark plug renewal requires a spark plug
socket which fits onto a ratchet spanner. This
socket is lined with a rubber grommet to
protect the porcelain insulator of the spark
plug and to hold the plug while you insert it
into the spark plug hole. You will also need a
wire-type feeler gauge to check and adjust
the spark plug gap and a torque wrench to
tighten the new plugs to the specified torque
(see illustration).
2If you are replacing the plugs, purchase the
new plugs, adjust them to the proper gap and
then replace each plug one at a time. Note:
When buying new spark plugs, it’s essential
that you obtain the correct plugs for your
specific vehicle. This information can be found
in the Specifications Section at the beginning
of this Chapter, on the Vehicle Emissions
Control Information (VECI) label located on the
underside of the bonnet (where fitted)or in the
owner’s manual. If these sources specify
different plugs, purchase the spark plug type
specified on the VECI label because that
information is provided specifically for your
engine.
Every 7500 miles or 6 months 1•7
1
3.7 The oil drain plug (arrowed) is located
at the rear of the sump - use a ring
spanner or socket to remove it3.13 The oil filter is located on the left side
of the engine - use a filter wrench for
removal (tighten the new filter by hand)3.15 Lubricate the oil filter gasket with
clean engine oil before refitting the filter
3261 Jaguar XJ6
Note: It is
antisocial and
illegal to dump oil
down the drain.
To find the
location of your
local oil recycling
bank, call this
number free.

3Inspect each of the new plugs for defects. If
there are any signs of cracks in the porcelain
insulator of a plug, don’t use it.
4Check the electrode gaps of the new plugs.
Check the gap by inserting the wire gauge of
the proper thickness between the electrodes
at the tip of the plug (see illustration). The
gap between the electrodes should be
identical to that listed in this Chapter’s
Specifications or on the VECI label (as
applicable). If the gap is incorrect, use the
notched adjuster on the feeler gauge body to
bend the curved side electrode slightly (see
illustration).
5If the side electrode is not exactly over the
centre electrode, use the notched adjuster to
align them.Caution: If the gap of a new plug must be
adjusted, bend only the base of the earth
electrode - do not touch the tip.
Removal
6To prevent the possibility of mixing up
spark plug leads, work on one spark plug at a
time. Remove the lead and boot from one
spark plug. Grasp the boot - not the lead - as
shown, give it a half twisting motion and pull
straight up (see illustration).
7If compressed air is available, blow any dirt
or foreign material away from the spark plug
area before proceeding (a common bicycle
pump will also work).
8Remove the spark plug (see illustration).9Whether you are replacing the plugs at this
time or intend to re-use the old plugs,
compare each old spark plug with the chart
shown on the inside back cover of this manual
to determine the overall running condition of
the engine.
Refitting
10Prior to refitting, apply a coat of anti-seize
compound to the plug threads (see
illustration). It’s often difficult to insert spark
plugs into their holes without cross-threading
them. To avoid this possibility, fit a short piece
of 3/8-inch internal diameter (ID) rubber hose
over the end of the spark plug (see Haynes
Hint). The flexible hose acts as a universal
joint to help align the plug with the plug hole.
Should the plug begin to cross-thread, the
hose will slip on the spark plug, preventing
thread damage. Tighten the plug to the torque
listed in this Chapter’s Specifications. In the
absence of a torque wrench, tighten each
plug until you feel it seat, and then by a further
quarter-turn only. Do not overtighten the
spark plugs.
11Attach the plug lead to the new spark
plug, again using a twisting motion on the
boot until it is firmly seated on the end of the
spark plug.
12Follow the above procedure for the
remaining spark plugs, replacing them one at
a time to prevent mixing up the spark plug
leads.
1•8Every 7500 miles or 6 months
4.4a Spark plug manufacturers
recommend using a wire-type gauge when
checking the gap - if the wire does not
slide between the electrodes with a slight
drag, adjustment is required4.4b To change the gap, bend the side
electrode only, as indicated by the arrows,
and be very careful not to crack or chip the
porcelain insulator surrounding the
centre electrode4.6 When removing the spark plug leads,
grasp only the boot and use a
twisting/pulling motion
4.8 Use a spark plug socket with a long
extension to unscrew the spark plugs
3261 Jaguar XJ6
4.1 Tools required for changing
spark plugs
1 Spark plug socket - This will have special
padding inside to protect the spark plug
porcelain insulator
2 Torque wrench - Although not mandatory,
use of this tool is the best way to ensure
that the plugs are tightened properly
3 Ratchet - to fit the plug socket
4 Extension - Depending on model and
accessories, you may need special
extensions and universal joints to reach
one or more of the plugs
5 Spark plug gap gauge - This gauge for
checking the gap comes in a variety of
styles. Make sure the gap for your engine
is included
4.10 Apply a coat of anti-seize compound
to the spark plug threads
A length of 3/8-inch ID rubber hose will
save time and prevent damaged
threads when refitting the spark plugs