1998 JAGUAR X308 fuel pressure

        309: Exhaust  Syst
em
 
 
             309‐00:  Exhaust  System 
                 Specification  
                 Description  and  Operation  
                     Exhaust System  
                 Diagnosis  and  Testing  
                     Exhaust System  
                 Removal and  Installation  
                     Catalytic Converter  LH  (17.50.15)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA V8  ‐ AJ27  
                     Catalytic Converter  LH  (17.50.15)  ‐ 4.0L  SC  V8 ‐ AJ26,  Vehicles  With:  
            Supercharger  
                     Catalytic Converter  RH  (17.50.16)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA V8  ‐ AJ27  
                     Catalyt
ic Converter  RH  (17.50.16)  ‐ 4.0L  SC  V8 ‐ AJ26,  Vehicles  With:  
            Supercharger  
                     Catalytic Converter  Gasket  LH  (17.50.06)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA  V8  ‐ AJ27  
                     Catalytic Converter  Gasket  LH  (17.50.06)  ‐ 4.0L  SC  V8 ‐ AJ26  
                     Catalytic Converter  Gasket  RH  (17.50.07)  ‐ 3.2L  NA V8  ‐ AJ26/4.0L  NA  V8  ‐ AJ27  
                     Catalyt
ic Converter  Gasket  RH  (17.50.07)  ‐ 4.0L  SC  V8 ‐ AJ26  
                     Front Muffler  (30.10.18)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA V8  ‐ AJ27  
                     Front Muffler  (30.10.18)  ‐ 4.0L  SC  V8 ‐ AJ26  
                     Intermediate  Muffler LH  (30.10.15)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA  V8  ‐ AJ27  
                     Intermediate  Muffler LH  (30.10.15)  ‐ 4.0L  SC  V8 ‐ AJ
26  
                     Intermediate  Muffler RH  (30.10.16)  ‐ 3.2L  NA  V8  ‐ AJ26/4.0L  NA  V8  ‐ AJ27  
                     Intermediate  Muffler RH  (30.10.16)  ‐ 4.0L  SC  V8 ‐ AJ26  
                     Muffler and Tailpipe  LH (30.10.22)  
                     Muffler and Tailpipe  RH (30.10.52)  
 
        310:  Fuel  System  
 
             310‐00:  Fuel  System  ‐ General  Information  
                 General Procedures  
                     Fuel System  Pressure  Check  
                     Fuel Tank  Draining  
 
  
Fuel  Sy stem  Pres
sure
 Release  

General Information - Terminology Glossary

Description an
d Operation

This glossary of terms is intended to cover emissions-related (to SAE J 1930) term inology, and other abbreviations that may
be used in this manual.
The required term may be looked-up in th e left-hand column, and subsequent columns give the standard acronym, unit or
abbreviation, and definition.
Te rm
(s)
Acr
ony
m /
Unit /
Abbreviation
De fi
nition
A
Accel
e
rator Pedal
AP
Af
ter Botto
m Dead
Center
ABDCEvent occurri ng after
BDC
Af
ter Top Dead CenterATDCEvent occurri ng after
TDC
Ai
rbag /
Supplementary
Restraint System
Airbag, SRSAi rbag restraint system for
dr
iver and front seat passenger
Air Cleane rACL
Air ConditioningA/C
Air Conditioning Con t
rol
Module
A/CCMModule c
ontrolling air conditioning, heating and ventilation
Air Conditioning SignalACSA
i
r conditioning compressor clutch operation is signalled to the ECM which
induces idle speed corrections to co mpensate for engine load changes
Alternating cu
rrent
ac
Ai
r Fuel R
atio
AFRN
omi
nally 14.7 parts air to one part fuel
Ampe
reASI unit of current
Ampere hourAhA current of one ampere
fl
owing for one hour
Anti-Lock Braking SystemABSS
y
stem which prevents wheel lock-up
under braking by sensing lack of
rotation of a wheel(s) and divertin g fluid pressure away from it (them)
ABS Control Mo
dule
ABS CM
ABS /
T
raction Control
Control Module
ABS / T
C CM
Atmosph
e
re
atmU
n
it of pressure (1.01325 bar)
Au
to
matic Stability
Control
ASCA form of vehicle
control
in which the ECM reduces en gine torque to control
wheel-spin
B
Baro me
tric Absolute
Pressure Sensor
BAR OSensor measuring the pressure of surr ou
nding air at any given temperature
and altitude
Bat t
ery positive voltage
B+The posi
ti
ve voltage from a battery or
any circuit connected directly to it
Before Bottom Dead
CenterBBDCEvent occurri ng before BD
C
Before Top Dead

Center
BTD
CEvent (usual ly
ignition) occurring before TDC
Blowe
rBLRDe
vice which supplies a current of air at
moderate pressure, e.g. heater or
A/C blower
Body Processor M
odule
BPMControl modu
le
for body electrical systems, e.g. interior lamps, windshield
wash / wipe control
Bott om D
ead Center
BD
CLowest poin t of piston
travel in a reciprocating engine
Brake hors
epowe
r
bhpEffecti
ve horsepower devel
oped by an
engine or motor, as measured by a
brake applied to its output shaft
Brake Mean Effective
Pres sureBME PThat p
art of the effective
pressure developed in a cyli nder that would result in
a cylinder output equal to the bhp of the engine
Brake On/ O
ff
BOOIn
dic
ates the position of the brake pedal
Br
it
ish Standard
BSStan
dar
d specification issued by the British Standards Institution
Br
it
ish Standard
Automotive
BSAu
BusTopology of a commu n
ication network
Bypass
AirBPAMechanica l
control of throttle bypass air
C
Camshaft Posit
i
on Sensor
CMPSIndi
cat
es camshaft position
Canadian Motor
V
ehicle
CMVSS

Safety Standard
Canister PurgeCANPControls pu
rging of the EVAP canister
Carbon dioxideCO2Colorless gas with

a density of a
pproximately 1.5 ti mes that of air
Carbon mon
oxide
COPoi
sonous gas produced as the re
sult of incomplete combustion
Case G
round
CSE GNDControl modu
le casing ground
Catal

ytic converter
In
-line exhaust system device used to reduce the level of engine exhaust
emissions
Ce
lsius
CSI ter
m for the Centigrade scale, with
freezing point at zero and boiling point
at 100°
Central
Processor Unit
CPUTh
e section of a computer that contai
ns the arithmetic, logic and control
circuits. It performs arithm etic operations, controls instruction processing, and
provides timing signals and other housekeeping operations
Cl
osed Loop
CL
Cl

osed Loop System
CLSControl
system with one
or more feedback loops
Col
umn/Mirror Control
Module
C/MC
M
Control ModuleCMA

self-contained group of electrical/electronic components, designed as a
single replaceable un it, and controlling one or more processes
Controll
er Area Network
CANA
communication system which allows control modules to be linked together
in a network.
Crankshaft Posi
tion
Sensor
CKPSGenerates crankshaft positi on informa
tion in conjunct
ion with the CKPTR (also
generates speed information in certain applications)
Crankshaft Posi
tion
Timing Ring
CKPT
R
Toothe
d ring which
triggers the CKPS
Crankcase Ventila
tion
System
CVSys
tem which scavenges camshaft cover and crankcase emissions and feeds
them into the inlet manifold
Cubic ce nt
imeter
cm
3
Curb weightWe

ight of vehicle with fuel, lubrican
ts and coolant, but excluding driver,
passengers or payload
D
Dat
a Link Connector
DLCConne
ctor providing access and/or control of the vehicle information,
operating conditions, and diagnostic information
De
gree
deg, °Angle or tempe
rature
D

epartment of
Transportation (US)
DO
T
D

epartment of Transport
(UK)
DTp
De
utsche In
stitut für
Normung
DINGerman stand
ards regulation body
Di

agnostic Module
DMSuppl
emental Restraint System (non-c
ontrolling) module for diagnostics
overview
Di
agnostic Test Mode
DTMA le
vel of capability in an OBD system.
May include different functional states
to observe signals, a base level to re ad DTCs, a monitor level which includes
information on signal levels, bi-directional control with on /off board aids, and
the ability to interface with remote diagnosis
Diagnostic Trouble CodeDTCAn al
pha/numeric identifier for a fault
condition identified by the On-Board
Diagnostic (OBD) system
D
ial test indicator
DTIA mechan
ical measuring
instrument, with a rotary indicating pointer
connected to a linear operating probe
D
ifferential pressure
Pressure di
fference betwee
n two regions e.g. between intake manifold and
atmospheric pressures
D
ifferential Pressure
Feedback EGR
DP
FE
An
EGR system that monito
rs differential EGR pressure across a remote orifice
to control EGR flow
D
irect current
dcCurrent which f
lows in on
e direction only, though it may have appreciable
pulsations in its magnitude
Du
al linear switch
DLSJ
-gate switch connected to the TCM on SC vehicles
E
EGR

Temperature EGRT
Sensor
EGRTSens
ing EGR function based on temperature change
EGR Vacu

um Regulator
EVRControls EGR
flow by changi
ng vacuum to the EGR valve
EGR Valve
Position
EVPAn EGR
system that direct
ly monitors EGR valve position to control EGR flow
Electrically E
rasable
Programmable Read-Only
Memory
EEP
ROM

Electrically Programmable
R
ead-Only memory
EPROM
Ele
c
tronic Secondary Air
Injection
EAIRA p
ump-driven system for providing seco
ndary air using an electric air pump
Engine C
ontrol Module
ECM
End of dashEODR
e
ferring to a vehicle fascia, eg EOD air vent
Engine
C
oolant Level
ECL
Engine
C
oolant
Temperature
ECT
ECT Sen s
or
ECTSTherm
i
stor which provides engine coolant temperature signal to the ECM to
trigger enrichment circuits which increase injector 'on' time for cold start and
warm-up
Engine s
peed
RP
M
Environ m
ental Protection
Agency
EPA
Evaporative EmissionEVAPSy stem designed to prevent fu
el vapor from escaping into the atmosphere.
Typically includes a charcoal filled canister to absorb fuel vapor
Evaporative Emission
Control ValveEVAPP
Exhaust G
as Recirculation
EGRSys
t
em which reduces NOx emissions by adding exhaust gases to the
incoming fuel/air charge
Exhaus t G
as Recirculation

Solenoid Vacuum Valve
EGRS
Exhaus t G
as Recirculation

Temperature Sensor
EGRT Sen s
or
Exhaus
t G
as Recirculation

Valve
EGRV
F
F a
n Control
FCEngine

cooling fan control
F
e
deral Motor Vehicle
Safety Standard (US)
FMV S
S
Fi
gur
e
Fi
g.Illustrati
on reference
Flash
E
lectrically Erasable

Programmable Read-Only
Memory
FEE PR
OM
Flash
E
rasable
Programmable Read-Only
Memory
FEP R
OM
Flywhee
l
Sensor
CKFSSens
or moun
ted so as to be
triggered by each flywheel ring gear tooth to give
an engine speed signal
Fue l
Injectors
FISol
e
noid operated devices that spray a metered quantity of fuel into the inlet
ports
F u
el Pressure Regulator
Control
FP RCControls fuel pressure regu l
ator; used primarily to
give extra fuel at cold
start-up
Fue l
Pump
FP
Fue
l
Pump Monitor
FP
MMonitors operation of fuel pump
Fue l
Pump Relay
FP
R
Fu
el rich/lean
Q
u
alitative evaluation
of air/fuel ratio based on a ratio known as
stoichiometry, or 14.7:1 (Lambda)
F u
ll Scale Deflection
FSDTh
e
maximum indication point on
an analogue meter or gauge
G
Gene
rator
GENRot
a
ting machine which converts mechanical energy into electrical energy
G
r
amme centimeter
gcm
Gramm
e
(force)
gf
Gramm
e
(mass)
g
GroundGNDEle
c
trical conductor used
as a common return for an electrical circuit or
circuits, and with a relative zero potential
H
Hard f a
ult
A
fau
lt currently present in the system
HeadlampHL
Heat
ed Oxygen
Sensor
HO2SElectrically
h
eated oxygen sensor which induces fueling corrections
Hertz (frequency)HzFrequ
e
ncy, one cycle per second
High
Moun
ted Stoplamp
HMSL

High
tension (electrical)
ht
Hourh
Hydro

carbon
HC
I
Idl

e Air Control
IACEl
ectrical control of throttle bypass air
Idl

e Air Control Valve
IACVStepper motor dri
ven device which vari
es the volume of air by-passing the
throttle to maintain the programmed idle speed
Ignitionign
Ignition am
plifier
IAD
evice which amplifies the i
gniti
on system output
Ignition groundIGN GND
In

ertia Fuel Shut-off
IFSAn
inertia system that shuts off the fuel supply when activated by pre-
determined force limits brough t about by (e.g.) collision
In
ertia Fuel Shut-off
Switch
IFSSShut
s down fuel and ignition systems in the event of a vehicle impact
Inta

ke air
Air drawn t
hrough a cleaner and distri
buted to each cylinder for use in
combustion
InputI/PAn
electrical input signal to a controlling device
Inta

ke Air Temperature
IATTem
perature of intake air
Inta

ke Air Temperature
Sensor
IATSDe
vice used to measure IAT
Inta

ke Air Temperature
Sensor Ignition
IATSITherm
istor which signals the ECM to retard
the ignition timing in response to
high inlet air temperatures
Inta
ke Air Temperature
Sensor Injection
IATSFTher
mistor which inputs air density information to the ECM
Internal diameteri.

dia
Inte

rnational Standards
Organization
ISO
K
Kilogramme (mass)kg
Kilogram
me (force)
kg
f
Ki

logramme force per
square centimeter
kg
f/cm2
Kilom

eter
km
Ki

lometer per hour
km
/h
Kilopasc

al
kP
a
KilovoltkV
Knock

Sensor
KSSens
or which detects the onset of detonation, and signals the ECM to retard
the ignition
L
Le
ft-hand
LH
Left-hand drive veh

icle
LHD
Le

ft-hand thread
LH Thd
Ligh

t Emitting Diode
LEDLigh
t-emitting semiconductor diode used
in alphanumeric displays and as an
indicator lamp
Liqu
id Crystal Display
LCDOp
tical digital display system, applied voltage to which varies the way the
crystals reflect light, thereby modifying the display
LiterL
Low ten
sion
ltPrim
ary circuit of the ignition system, linking the battery to the primary
winding in the ignition coil
M
Malfu
nction Indicator
Lamp
MILA
required on-board indicator to aler
t the driver of an emission related
malfunction
Mani
fold Absolute
Pressure
MAPAbsolute pressure o
f the intake manifold air
Mani

fold Absolute
Pressure Sensor
MAPSSensor loca
ted in the ECM and
ported to the intake manifold
Manifol
d Surface
Temperature
MST
Mass Ai
r Flow
MAFSy
stem which provides inform
ation on the mass flow rate of the intake air to
the engine
Mass Ai
r Flow Sensor
MAFSHot-wi
re sensor which monitors air flow
into the intake manifold for fueling
and ignition control
Maxim
um
max.

Meter (measurement)m
Me
tric (screw thread, e.g.

M8)
M
MicrofaradMFDUni t
of electrical capacitance, one millionth of a farad
Mi
ll
imeter
mm
Mi
ll
imeter of mercury
mm
Hg
Mill
isecond
ms
Min
i
mum
mi
n.
Min u
te
minut
e
Model YearMY
ModuleMSelf
contained group of electrical/electronic components which is designed as
a single replaceable unit
Modulating signalMDA sh
ift process signal to the TCM on SC vehicles
Motorized In
-Car
AspiratorMIAD e
vice which constantly samples cabi
n temperature by passing air over a
sensor, and communicates with the A/ CCM to modify A/C system performance
to suit
Mult i Prot
ocol Adaptor
MPAAn i
n
terpreter for the various data
languages present on a vehicle
N
Nati
onal Institute of
Occupational Safety and
Health (US)
NIO S
H
Ne
wto
n
NSI unit of force. 1
N = 0.224
8 pounds force
Ne
wto
n meter
NmSI unit of torque. Must not be
co
nfused with nm (nanometer)
Ni
tr
ous Oxide
NO
xCompounds of nit rogen and oxygen fo rmed at high temperatures. Major
sourc
e of exhaust-gas air pollution
No
n
-Volatile Random
Access Memory
NVR A
M
R
A
M which retains memory even
if power supply is interrupted
Normal
ly aspirated
F
u
eling system using intake air at atmo
spheric pressure; not supercharged or
turbocharged
N ormal
ly Closed
NC
N
o
rmally Open
NO
No
r
th American
Specification
NASVehicles f or sal
e in the USA and Canadian markets
Nu
mbe
r
No
.
O
Oc
cupational Safety and
Health Administration
(US)
OS H
A
O
n
-Board Diagnostic
OB
DA system that moni
tors some or all co
mputer input and output control signals.
Signal(s) outside the pre-de termined limits imply a fault in the system or a
related system
O n
-Board Refueling
Vapor Recovery
OR V
R
O
riginal
Equipment
Manufacturer
OE M
Outp
ut
O/
PAn electrical o u
tput signal from a controlling device
Ou
ts
ide diameter
o.
d
ia
O
xides of
nitrogen
NO
x
Oxygen senso
r
O2
SA s
ensor which detects oxygen content in the exhaust gases
P
Parameter Identifi
erPIDAn in
dex number referring to a parame
ter within a module without knowledge
of its storage location
Park N e
utral Position
PN
P
Park N e
utral Position
Switch
PN PSIndic
ates the selected non-drive modes of the (automatic) transmission
Part numberpart no.
Portable Diag
nostic Un
it
PD
UCompre hen
sive electrical diagnosis system specific to Jaguar vehicles
Posi
ti
on
po
s'n
Power As si
sted Steering
PASHydraul
i
c pump-assisted steering system
Power Steer
i
ng Pressure
PSP
Programmable Elect
r
onic
Control Units System
PECU SProcess whereb y
a common ECM is progra
mmed on the production line to suit
the market requirements of a particular vehicle
Programmable Read-O
nly

PROMRO
M with some provision for setting
the stored data after manufacture

Suspension System - General Informatio
n -
Lubric
ants, Fluids, Sealants and Adhesives
Front Suspension Dimensions
• NO
TE: When a component reaches its maximum / minimum dimension limit the component must be replaced.
Rear sus
p
ension Dimensions
•
NO
TE: When a component reaches its maximum / minimum dimension limit the component must be replaced.
Vehicle ride
height


R i
de height is measured from
the center of the wheel to the apex of the wheel arch, through the wheel center line.
Showroom is with a
ll fluids at full an
d 9 liters (9.5 US quarts) of fuel.
Curb is
with all fluids at full and a full tank of fuel.
All f
i
gures quoted assume a ±
15 mm (0.59in) anticipated bu ild variance and condition.
Whee
l Alignment - Front Camber - XJR Excluding NAS, and German Super-8

Al l the above fi
gures
are at "showroom" height. (See ride height section above).
Tires must be infl
ated
to normal pressure.
For additional informat ion, refer to Section 204
-04
Wheels and Tires
.
Whe
e
l Alignment - Front Camber - XJR NAS, and Comfort/Sport/Daimler Super-8
UnitSp
ecification
Loctite27
0
Greas eShell Retin a
x 'A'
Greas
eCastro l 'NT
R'
Com
p
onent
Di
mensi
on
Hub face
-
maximum run-out
0.
03
8 mm
Com
p
onent
Di
mensi
on
Hub face
-
maximum run-out
0.
05
7 mm
Mod
e
l
Mod
e
l Year
V
I
N RANGE
Mark
et
Sh
owroom mm(in)
Curb mm(i
n)
FromToFron
t
RearFr
on
t
Rear
Com
f
ort suspension
1
998
to 2003.5
8
123
17
F
595
25
All3
90 (
15.11)
3
84 (
15.11)
3
89 (
15.31)
3
73 (
14.68)
Sport su
spe
nsion
"""All3
89 (
15.31)
3
81 (
15.00)
3
88 (
15.27)
3
72 (
14.64)
XJR"""NAS3
89 (
15.31)
3
82 (
15.03)
3
88 (
15.27)
3
72 (
14.64)
XJR"""RO
W367 (
14.44)
3
65 (
14.37)
3
66 (
14.40)
3
58 (
14.09)
Supercharged super 8"""All3
89 (
15.31)
3
82 (
15.03)
3
88 (
15.27)
3
72 (
14.64)
XJR

Excluding NAS, and German Super-8
1998 to

2003.5
VIN - 812317 to F59525
Units
Cambe r
Left
- Hand
Rig
h
t - Hand
Bal
a
nce (RH - LH)
MinMaxMinMaxMinMax
All Right-Hand driv
e and JapanDegrees
/minutes
-
1
° 28'
-0
°
28'
-
1
° 13'
-
0
° 13'
-0
° 45'+1 °
15'
Decimal degrees-1.
4
7°
-0
.4
7°
-1
.2
2°
-0.
2
2°
-0
.7
5°
+1
.25
°
R
e
st of World
De
grees
/minutes
-
1
° 13'
-0
°
13'
-
1
° 28'
-
0
° 28'
-1
° 15'+0 °
45'
Decimal degrees-1.
2
2°
-0
.2
2°
-1
.4
7°
-0.
4
7°
-1
.2
5°
+0
.75
°
XJR

NAS, and Comfort/Sport/Daimler Super-8
1
998 to
2003.5
VIN - 812317 to F59525
Units
Cambe r
Left
- Hand
Rig
h
t - Hand
Bal
a
nce (RH -
LH)
MinMaxMinMaxMinMax
All Right-Hand drive and JapanDegrees
/minutes
-1°
02'-0
° 02'
-0°

47'
+0°

13'
-0° 45'+1°

15'
Decimal degrees-1.0
3°
-0.0
3°
-0.7
8°
+0.22
°
-0.7
5°
+1.25
°
USA, Canada an
d Mexico,
Dominican
Republic (NAS)
De grees
/minutes
-0°
32 '+0 °

28'
-1 °

02'
-0 °
02'
-1°
30 '+0 °

30'
Decimal degrees-0. 5
3°
+0
.47
°
-1
.0
3°
-0
.0
3°
-1.
5
0°
+0
.50
°
R
e
st of World
De
grees
/minutes
-0°
47 '+0 °

13'
-1 °

02'
-0 °
02'
-1°
15 '+0 °

45'

Decimal degrees-0. 7
8°
+0
.22
°
-1
.0
3°
-0
.0
3°
-1.
2
5°
+0
.75
°

Suspension System - General Information - Front Camber and Caster
Adjust
ment
Gen
eral Procedures
• NOTE: Before any work is commenced, th e vehicle must be checked to establish that it conforms to the Jaguar original
specification, e.g. wheels, ti res, tire pressures, etc.
• NOTE: The vehicle must be unladen and the fuel tank full when measuring suspension geometry.

1.
Road test the vehicle to establish the exact nature of the
complaint, e.g. pulling to one side, wander.
2. Measure the suspension geometry, fill in the 'Suspension
Geometry Record Form', and co ntact Jaguar Technical Support
for assistance.
3. Technical Support will give advice on the course of action to be
taken to rectify the problem.
4. Each lower wishbone pivots on and is secured to the front
crossbeam by two fulcrum bolts. A circular eccentric flange
formed under the hexagonal head of each fulcrum bolt, has
raised graduation marks to indicate radial position. A washer
with a 'D' shaped hole locates on a flat on the threaded section
of each bolt. This ensures that the washer rotates with the bolt,
maintaining an eccentric position corresponding with the
flanged head. The outer face of the washer is punch marked,
ensuring correct instal lation with the chamfered face inwards.
This permits the washer to rotate freely in the crossbeam cam
reaction plate during a djustm ent. Each fulcrum bolt and
washer are secured by a self locking nut.
On rotation of the bolt, lateral movement of the eccentric flange
and washer is restricted by the cam plate faces, forcing the bolt
shank to move laterally in the crossbeam slots. Lateral
movement of the bolt shank re sults in corresponding inward
and outward movement of th e wishbone arm, effecting
adjustment of wh eel alignment.
Rotation of the front fulcrum bolt principally adjusts wheel
caster angle, with a small amount of camber angle change.
Adjustment of the rear fulcrum bo lt mainly alters wheel camber
angle with a small amount of caster angle change.
On vehicles with VIN up to 833124, fulcrum bolt eccentric
flanges have raised graduation marks representing 15 degree
increments of bolt rotati on from 0 to 90 degrees.
On vehicles with VIN from 833125, the fulcrum bolt graduation
marks represent bolt shank ho rizontal movement in 1mm
increments from 0 to 3mm.
The upper wishbone and fulcrum shaft are not adjustable and
play no part in steering geometry adjustment.