catalytic converter JAGUAR XJ6 1994 2.G Workshop Manual

Introduction i
Term(s) Abbreviation Definition
(if applicable)
GLOSSARY OF TERMS
Previously used term(s) (or Eng-
lish Equivalent)
indicates camshaft position
device designed to hold dry material, e.g.
evaporative emission canister
controls purging of the EVAP canister
colorless gas with a density of approximately
1.5 times that of air
poisonous gas produced as the result of
incomplete combustion
camshaft
I
CID
sensor,
Hall sensor
Camshaft
Position
Camshaft Position Sensor CMPS
canister
Canister Purge CANP
Carbon Dioxide
CO2
I Case Ground I CSEGND
Carbon
Monoxide
camber
CO
Canadian Motor Vehicle Safety
Standard
caster
Catalytic Converter
Celsius
center
I
CMVSS
C
centimeters
I cm
trail built in to the geometry of a steered
roadwheel to give
it a caster - self-steering -
effect
caster,castor
color
columnlmirror control module I C/M CM
charge current
Closed Loop
Closed Loop System
Clutch
clutch disc, clutch disk
clutch
throwout bearing
connecting rod bearing
CL
CLS
a shaft on which phased cams are mounted.
Usually used to regulate opening and closing
of engine cylinder head valves
current developed by the generator
control system with one or more feedback
loops
device which uses mechanical, magnetic or
friction type connections to facilitate
engaging or disengaging
two shafts or
rotating members charging
current
Control
module casing ground
inclination of the plane of a wheel to the
vertical plane
ofthe vehicle. May be negative
or positive.
Also convex curvature across road surface
bearing (usually split, plain) at the lower end
of the connecting rod where
it connects with
the crankshaft big
end bearing
in
-line exhaust
system device used to reduce
the level of engine exhaust emissions
SI term forthe Centigradescale, with freezing Doint at zero and boilina Doint at looo
I centre
I centimetres
friction disc of a clutch assembly clutch
plate,
centre plate,
diaphragm spring to release the clutch disc
I colour
Issue 1 August 1994 X300 VSM 9

(if applicable) term(s) (or Eng- lish Equivalent)
N
National Institute of Occupational NIOSH Safety & Health (US)
Newton N SI unit of force. 1 N = 0.2248 pounds force
Newton meters Nm
SI unit of torque. Must not be confused with nm (nanometer)
compounds of nitrogen and oxygen formed
at high temperatures. Major source of
exhaust
-gas air-pollution
RAM which retains memory even if power
N
Ox
NVRAM
Memory supply is interrupted
normally aspirated fueling system using intake air at
atmospheric pressure; not supercharged or
turbocharged
Normally Closed NC
Normally Open NO
North American Specification NAS vehicles for sale
in the USA and Canadian
markets
0
I number I No.
octane number
I
I open circuit
I oriainal eauiDment manufacturer
I outside diameter OSHA
OBD
OEM
0. dia
OHC
oc
N Ox
02s
measure ofthe anti-knockproperties ofafuel
instrument which records the total mileage
covered by a vehicle
a system that monitors some or all computer
input and output control signals.
Signal(s) outside the pre-determined limits imply a
fault in the svstem or a related svstem
a circuit which does not provide a complete
path for flow of current
engine configuration with single camshaft
positioned above the valves
catalytic converter system that reduces
levels
of HC and CO
a sensor which detects oxygen content in the
exhaust gases mileometer
oilwav
EGO,
02 EOS,
EGS, OS, EGOS,
Lambda Sensor
Issue 1 August 1994 20 X300 VSM

0
Term(s) Abbreviation Definition
(if applicable)
Introduction i
Previously used term(s) (or Eng-
GLOSSARY OF TERMS
I lish Equivalent) A 3
Scan Tool
Seat Control Module
Secondary Air
Secondary Air Injection
Secondary Air Injection Bypass
..
Secondary Air -Injection Check
Valve
Secondary Air Injection
Diverter
Secondary Air Injection Magnetic
Clutch
Secondary Air Injection Pump
Secondary Air Injection Relay
Secondary Air Injection Switching
Valve
Security
& Locking Control Mod- ule
sedan
Sensor
Service Bulletin
Service Manual
Service Manual Preliminary
In-
formation Bulletin
Service Repair Operation
(number)
ST
SCM
AIR
AlRB
AI RC
AlRD
AIRPC
AlRP
AlRR
AIRS
SLCM
-
S
SE
SM
SMPlB
SRO
device that interfaces with and
communicates information on a data link
module controlling the seat motor systems
(not electric
raisejower-only seats)
air provided
to the exhaust system
system used for a period of time each time
the engine is started, unless certain
temperature criteria are met. Pumps air
directly into the exhaust system which
generates extra heat and reduces the time
taken for the catalytic converters to reach
operating temperature
vents secondary air to atmosphere
valve which prevents back
-flow of exhaust
gas to the AIR system when the system is
inoDerative
diverts secondary air to either the catalyst or
exhaust manifold
clutch mounted on the AlRP drive shaft
mechanically driven rotary vane
pump,
driven through the AIRPC
controls the injection of air into the exhaust
system
vacuum operated valve backing
-up the AlRC
module controlling the vehicle‘s security and
closure
-locking functions
passenger car having two or four doors, and
front and rear
seatsfor driver and passengers
generic name for a device that senses either
the absolute value or a change
in a physical
quantity such as temperature, pressure or
flow rate, and converts that change into an
electrical auantitv sianal
__
form of Service Bulletin specifically designed
to enable the rapid issue of temporary pages
for inclusion in the Service Manual
Number
generated by Jaguar Methods &
Techniques system which relates to the time
allowed to complete a repair operation.
Further information on the system can be
found
in the separate Jaguar Publications
(for each model range) entitled ‘Repair
Operat ion Times’. AIP,
AI,
Thermac, air injection sys-
tem
NRV, non-return
valve
air
pump clutch
AIP, air
pump
air injection relay
air switching
valve
saloon
Issue 1 August 1994 23 X300 VSM

Term(s) Abbreviation Definition Previously used
(if applicable) term(s) (or Eng-
lish Equivalent)
T
tachometer
Thermal Vacuum Valve
Three
-way Catalytic Converter
Three
-way + Oxidation Catalytic
Converter TWC + OC
Throttle
------I
Throttle Body TB
Throttle Position TP
Throttle Position Sensor TPS
throw
-out bearing
throw
-out fork
tie
-rod (steering)
timing
tire
top dead center TDC
torque converter
Transmission
Transmission Control Module
Transmission Control Switch
Transmission Oil Temperature TOT
Transmission Range TR
I Transmission Speed Sensor TSS
tread
trunk
turn indicator, turn signal lamp
two cycle a
circuit that provides input for an electronic
tachometer display
controls vacuum levels or routing based on
temperature
catalytic converter that reduces the levels of
HC,
CO & NOx
catalyticconverter systemthat has both TWC
and OC. Usually secondary air is introduced
between the two catalvsts
procedure whereby the performance of a
product is measured under various
conditions - - . -. . . - . . -
a valve for regulating the supply of a fluid,
usually air or an aidfuel mixture, to an engine
device containing the throttle
interprets throttle position and movement to
identify idle, acceleration and full
-power
demands
relationship between spark plug firing and
piston position, usually expressed
in crankshaft degrees BTDC or ATDC of the
compression stroke
device which, by its design, multiplies the
torque in a fluid coupling between an engine
and transmission
device which selectively increases or
decreases the ratio of relative rotation
between its
inDut and outDut shafts
controls the shifting pattern of the
(automatic) transmission
Modifies the operation of electronically
controlled transmissions
indicates temperature
of transmission fluid
the range in which the transmission is
operating
indicates rotational speed of transmission
output shaft or turbine
shaft
track between tire contact centers; not to be
confused with tire contact tread pattern
principle of engine which fires every second
stroke of the piston cat
cat, dual bed
Throttle poten
-
tiometer, TPS, TP
clutch release
bearing
clutch release
lever
track rod
tvre
TCC, CCC, CCO,
LUS, MLUS,
MCCC
transmission
ECU
track boot, luggage
compartment
direction indica
- tor
two stroke
Issue 1 August 1994 26 X300 VSM

Introduction
Term(s) Abbreviation Definition
(if applicable)
n GLOSSARY OF
Previously used term(s) (or Eng-
lish Equivalent)
W
Warm-up Oxidation Catalytic
Converter
Warm
-up Three-way Catalytic
Converter
watts
wet sleeve
wheelslip
Wide Open Throttle
windshield
wrist pin (also
piston pin)
XYZ
wu-oc
wu-Twc
W
WOT
catalytic converter system designed to lower
HC and CO emissions during the warm
-up
period. Usually located in or near the
exhaust manifold
catalytic converter system designed to lower
HC, CO and
NOx emissions during the
warm
-up period. Usually located in or near
the exhaust manifold
SI unit of power (1 hp = 745.7 watts)
thin walled hard metal cylinder supported at
cylinder head and crankshaft ends; in contact
with coolant wet liner
I wheelspin
full throttle
Dosition
pin which connects the connecting rod to the
piston, and permits articulation between the
two. windscreen
gudgeon pin
Issue 1 August 1994 28 X300 VSM

Exhaust System (AJ16)
9
/ 7 I
3;

Fig. 1 Components of the Exhaust System (AJ16 Normally aspirated)
J?3-Z2l
Heated oxygensensorsarefittedtothedownpipeassembly (1 Fig.l)which isconnectedtothemanifold (2 Fig.1). There
are two sensors for the ROW and Japan (3 Fig.1) and two additional sensors (4 Fig.1) for NAS markets.
The sensors are located upstream and downstream of catalytic converters.
Apart from two heated oxygen sensors, the exhaust system for vehicles destined for the Japanese market are also
fitted with two exhaust gas temperature sensors
(5 Fig.1).
The exhaust system is held in a predetermined position by a fixing arrangement to the manifold by exhaust centre
mountings (6 Fig.l), by rear axis mountings (7 Fig.l), and tail pipe mountings (8 Fig.1).
Clamps (9 Fig.1) used on each slip joint are welded to the pipes and tightened to a higher torque setting than non- welded clamps.
The exhaust system must be free of leaks, binding, grounding and excessive vibrations. These conditions are usually
caused by loose, broken, or misaligned clamps, shields, brackets, or pipes. Should any of these conditions
exist,check the exhaust system components and alignment. Adjust and renew if necessary. Do not attempt to service brackets,
clamps and insulators.
Issue 1 August 1994 2 X300 VSM

Also look for loose and rusted flange connections, loose or damaged exhaust shields
or clamp and loose or broken exhaust outlet pipe brackets.
6.1.2.1 Symptom Chart
I Condition I Possible Cause
Noises and exhaust fumes Exhaust leak.
Misaligned exhaust.
Loose clamps or fasteners.
Restricted exhaust system.
Electronic engine controls.
Fuel System.
Restricted exhaust system.
Engine lacking
power Ignition system.
Exhaust System (AJ16)
6.1.2 DIAGNOSIS AND TESTING
m: THE NORMAL OPERATING TEMPERATURE OF THE EXHAUST SYSTEM IS VERY HIGH. NEVER ATTEMPT
TO SERVICE ANY PART OF THE SYSTEM UNTIL IT HAS COOLED. EXHAUST GASES CONTAIN CARBON
MONOXIDE WHICH CAN BE HARMFUL TO HEALTH AND ARE POTENTIALLY LETHAL. LEAKS MUST BE
REPAIRED IMMEDIATELY.
NEVER OPERATE THE ENGINE
IN ENCLOSED AREAS.
External leaks in the exhaust system are often accompanied by noises and exhaust fumes, therefore a visual inspection
usually detects the location of the leak. When checking for exhaust leakage or noise, inspect the entire system for
burned
-out holes, loose or corroded clamps, muffler or exhaust inlet pipe.
Examine the under body for greyish
-white or black exhaust soot which indicates the exhaust leakage at that point.
The effect of a small leak can be magnified by holding a rag over the tailpipe outlet while listening to the leak.
If this is carried out, ensure that gases are not inhaled
-see WARNING.
When testing for a rattle or vibration condition it is helpful to use a rubber mallet. Tap on the exhaust components to
simulate the bouncing action of the exhaust while watching for exhaust-to-body /chassis contact.
6.1.2.2 Test A, Exhaust Leakage or Noise
Test Step
Step
1A Clamps and Brackets
Check for broken or loose clamps and/or exhaust
outlet pipe frame brackets.
Are clamps and exhaust outlet pipe frame brackets
OK?
Step 2A System Components
Check catalytic converters, muffler.
Are system components OK?
Step 3A Exhaust Manifold
Inspect exhaust manifold for loose fasteners and
cracks.
Is exhaust manifold OK?
Action
Refer to Test Step 1A.
Go to Test Step IB, Restricted exhaust system test. .-
Go to Test Step 1B
Result Action
yes
1
Go to Step 2A
no Service and renew as necessary.
Restart engine.
If noise still exists
go to Step 2
yes Go to step 3A
no Renew exhaust outlet pipe frame brackets, exhaust
inlet pipe and/ or muffler as necessary.
If noise still persists, go to Step 3
yes
no Go to Test Step 1B Restricted exhaust system test.
Tighten fasteners or renew exhaust manifold.
X300 VSM 5 Issue 1 August 1994

Exhaust
ridion in Exhaust Systems
Test Step
Step
1B Visual Inspection
s the exhaust system visually OK?
Step 28 Vacuum Test
Attach a Vacuum Gauge or equivalent to the intake
manifold vacuum source.
Eonnect a Tachometer or equivalent.
Start engine and gradually increase speed to
2OOOrpm with transmission in neutral.
Is neutral vacuum above 53.8kPa (16 in. Hg)?
Step 38 Vacuum Test Exhaust Disconnected
rurn engine OFF.
Disconnect exhaust system at the exhaust mani-
fold.
Repeat vacuum test.
Is the manifold vacuum above 53.8kPa (16 in. Hg)?
Step 4B Vacuum Test Catalytic Converter(s1 on,
Mufflers off.
+
6.1.2.3 Test B, Rest1
Turn engine OFF.
Reconnect exhaust system at the exhaust manifold.
Disconnect muffler
Repeat vacuum test.
Is the manifold vacuum above 53.8kPa (16in. Hg)?
System (AJ 1 6)
Resutt
Yes
No
Yes
No
Yes
No
Yes
No
Action
Go to Step 2 B
Renew any collapsed exhaust components. Go to
Step
2
Refer to EDM
Go to Step 3
Exhaust System (AJ16)
6.1.2.3 Test B, Restridion in Exhaust Systems
Go to Test Step 4B
Renew muffler and retest.
Renew catalytic converter.
Issue 1 August 1994 6 X300 VSM

Exhaust System (V12)
6.2.1 GENERAL DESCRIPTION
6
4 5
J30-234
Fig. 1 Plan View of Exhaust system
'he low
-loss catalytic converter exhaust system for the VI2 engine comprises catalyst/downpipe assembly with addi- tional secondary catalytic converters (1 Fig.11, a underfloor catalytic converter assembly (2 Fig.1) complete with heat
shield (3 Fig.l), an intermediate muffler section (4 Fig.1) and a rear muffler section (5 Fig. 1).
On non-catalytic converter systems, the downpipe/catalyst assembly is fitted with conventional twin branch down- pipes (6 Fig.11, hence there are no oxygen sensors or exhaust gas temperature sensors.
Conventional mufflers are fitted in place of the underfloor converters.
X300 VSM 1 Issue 1 August 1994

b Exhaust System (V12)
8
Fig.

P
Components of the Exhaust System
130 -2 33
Two heated oxygen sensors are fitted to the downpipe assembly (1 Fig.1) which is connected to the manifold and two
on the underfloor catalytic converter assembly in front of the catalysts. There are two sensorsfor the ROW and Japan
markets (2 Fig.1) and two additional sensors (3 Fig.1) for the NAS markets.
The sensors are located on A
-bank and B-bank, upstream and downstream of catalytic converters.
Apart from two heated oxygen sensors, the exhaust system for vehicles destined for the Japanese market are also
fitted with two gas temperature sensors
(4 Fig.1).
The exhaust system is held in a predetermined position by a fixing arrangement to the manifold by exhaust centre
mountings (5 Fig.l), by rear axis mountings (6 Fig.1). and tail pipe mountings (7 Fig.1).
Clamps (8 Fig.1) used on each slip joint are welded to the pipes and tightened to a higher torque setting than non- welded clamps. ~ ~~~
Issue 1 August 1994 2 X300 VSM