1998 JAGUAR X308 vacuum

R
emove the drain tray.
6. Lower the vehicle.

7. Inst
all the cooling system va
cuum refill adaptor to the
expansion tank.

8. Inst
all the vacuum filler gauge to the cooling system
vacuum refill adaptor.

9. Inst
all the venturi tube assembly to the vacuum filler gauge.

10. Connect a regulated compressed air supply to the venturi
tube assembly.

11. P
osition the evacuated air hose into a container.

12 . N
OTE: Make sure the coolant su
pply valve is in the closed
position on the vacuum filler gauge assembly.
• NOTE: The coolant vacuum fill t ool needs an air pressure of 6
to 8 bar (87 to 116 psi) to operate correctly.
• NOTE: Small diameter or long airlines may restrict airflow to
the coolant vacuum fill tool. Open the air supply valve.

13 .
NOTE
: Make sure the coolant supply hose is positioned
into a container of fifty perc ent mixture of Jaguar Premium
Cooling System Fluid or eq uivalent, meeting Jaguar
specification WSS M97B44-D an d fifty percent water. Make
sure no air can enter the coolant supply hose.
Open the coolant supply valve for 2 seconds to prime the
coolant supply hose.

14 . Apply air
pressure
progressively until the arrow on the
vacuum filler gauge reac hes the green segment.
15. Close the air supply valve.

Vehic
les with supercharger


16
.
Allow one minute to check the vacuum is held.
Di
sconnect the air supply.

17
.
NOTE: Close the coolant supply valve when the coolant
expansion tank MAX mark is reached or coolant movement has
ceased.
Open the coolant supply valve and allow the coolant to be
drawn into the system.
18. Remove the vacuum filler gaug e and cooling system vacuum
refill adaptor assembly.
19. Install the coolant expansion tank pressure cap.
20. NOTE: To ensure that air is not drawn into the system during
the following operations, do not remove the coolant expansion
tank pressure cap whilst the supe rcharger filler plug is open.
• NOTE: Place a suitable cloth ar ound supercharger fill port.
Top up the superc harger coolant.
1. Remove the filler plug an d discard the sealing washer.
2. Top up the coolant through the supercharger fill port.

Pa
rts List
The pressure regulator is a diap hragm-operated valve that regula tes fuel-rail pressure at 3,0 bar above the intake manifold
pressure. A pipe connects the throttle induction elbow to the pressure regulator to provide the vacuum control signal. On
supercharged engines, the pressure regulator vacuum feed is taken from the top of the supercharger outlet duct.
The regulator is fitted between the rear end of the right-hand fuel rail (bank 1) and the fuel return line to the tank.
Circuit Diagram, Fuel Injection Syst em - Normally Aspirated Vehicles

Ite
m
Par
t
Number
De
scr
iption
1—F
u
el Return
2—F
u
el Pressure Regulator
3—Inta
k
e Manifold Pressure

C2: CHECK THE FUEL
PUMP 2 RELAY TO ECM CIRCUIT
Di

sconnect the battery negative terminal.
1

D
isconnect the ECM electrical connector, EM13.
2

Meas
ure the resistance between the rela
y base, pin 02 and EM13, pin 09 (KB).
3

Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the

DTC. TEST the system for normal operation.
No INSTALL a new fuel pump 2 relay. CLEAR the DT C. TEST the system for normal operation.
P
INPOINT TEST D : CHECK THE FUEL PRESSURE REGULATOR FUNCTION
CAUTI
ON: Do not run the engine for more than
30 seconds with the vacuum hose disconnected.
T
EST CONDITIONS
D
ETAILS/RESULTS/ACTIONS
D

1: CHECK FOR FUEL PRESSURE CHANGE
WHEN THE REGULATOR IS DISCONNECTED
Connect a
fuel pressure gauge set,
REFER to Section 310
-00
Fuel System
-

General Informati
on
. 1

St
art the engine.
2

N
ote the fuel pressure readin
g with the fuel pressure regu lator vacuum hose connected.
3

Di
sconnect the fuel pressu
re regulator vacuum hose.
4

N
ote the new reading.
5

Doe
s the fuel pressure increase when the hose is disconnected?
Yes Check for DTCs. Carry out the pinpoint tests indicated.
No INSTALL a new fuel presssure regulator. TEST the system for normal operation.
P
INPOINT TEST E : DTC P1230;
FUEL PUMP RELAY MALFUNCTION
•
NOTE: This DTC applies only to the N/A system si
ngle fuel pump, and the S/C system fuel pump 1
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
E1

: CHECK THE FUEL PUMP
RELAY BATTERY SUPPLY
R
emove the fuel pump relay.
1

Meas
ure the voltage between the
relay base, pin 03 and GROUND.
2

Is th
e voltage less than 10 volts?
Yes REPAIR the circuit between the rela y base, pin 03 and the battery power bus. This circuit includes the
trunk fuse box and the high power protection module . For additional information, refer to the wiring
diagrams. CLEAR the DTC. TEST th e system for normal operation.
No GO to E2
.
E2
: CHECK THE FUEL PUMP RELAY IGNITION SWITCHED SUPPLY
Turn the ignition swi

tch to the
ON position.
1

Meas
ure the voltage between the
relay base, pin 01 and GROUND.
2

Is th
e voltage less than 10 volts?
Yes REPAIR the circuit between the rela y base, pin 01 and battery. This circuit includes the trunk fuse box,

fuse 16 of the left-hand fuse box, the ignition po
sitive relay and the high power protection module.
For additional information, refer to the wiring diagrams. CLEAR the DTC. TEST the system for normal
operation.
No GO to E3
.
E3
: CHECK THE FUEL PUMP RELAY TO
ECM CIRCUIT FOR HIGH RESISTANCE
Di
sconnect the battery negative terminal.
1

D
isconnect the ECM electrical connector, EM83.
2

Meas
ure the resistance between EM83, pi
n 04 (WR) and the relay base, pin 02.
3

Is th
e resistance greater than 5 ohms?
Yes REPAIR the high resistance circuit. For additional information, refer to the wiring diagrams. CLEAR the
DTC. TEST the system for normal operation.
No

INSTALL a new fuel pump relay. CLEAR the DTC. TEST the system for normal operation. If the DTC is
repeated, contact dealer technical support for advice on possible ECM failure.

Fuel Char
ging and Controls - Throttle Body
Re
mo
val and Installation
Remov
a
l
• C
A
UTIONS:
When the throttle body is being replaced by a unit with the part number suffix ' BA', and carrying a sticker such as the
illustration below, then the usual cleaning procedure is NOT to be carried out. These thro ttle bodies have a molykote
coating which will be damaged by normal cleaning procedures. Refer to the latest service action s for further information.
This process assumes the use of the original throttle ca ble. The cable setting procedure in this instance is NOT
appropriate for a new cable; see 19.20.06.

1. Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).
2. Remove air cleaner cover / in take assembly; refer 19.10.30

3. Disc
onnect connectors and vacuum pipe.

4. Ro
tate throttle quadrant to allow disconnection of inner cable.
5. NOTE: Do not disturb adjusting nut
Release throttle cable locking nut and displace outer cable from

4. Inst
all coolant hoses.

5. R
eposition outer cable
to abutment bracket.
Install but do not tigh
ten adjusting nut.

6. CAUTI
ON: Under no circumst
ances should quadrant be
held clear of throttle stop by cable tension.
• NOTE: Make sure ther e is neither tension nor slack in the cable.
Install throttle cable.
Tigh
ten locknut without altering setting or introducing
twist into the cable outer.
7. Connect conn
ectors and vacuum pipe.

P
arts List
CAUTION: Do not attempt to renew or adjust the throttle cable without consulting the relevant procedure. Two
procedures apply: reconnection of an original cable (19.70.04) or the fitting of a new cable (19.20.06).
The filtered air from the intake duct is drawn downwards through the throttle body to the intake elbow on which the throttle
body is mounted. The airflow through the throttle body is vari ed by the electrically operated throttle valve according to
driver demand and engine mana gement system requirements.
The throttle body assembly has the following features:
Con
vential cable operated input shaft connected to the accelerator pedal.
M

echanical guard to limit throttle angl
e should driver demand exceed ECM co ntrolled parameters and a mechanical
back-up in the event of a throttle motor failure.
Vacuum actuator for operation of the mech anical guard in cru
ise control mode.
Thr

ottle valve (blade) to regula
te air flow into the engine.
Thermostatic air valve to allow and con
t
rol air by-pass around the throttle.
D
C electric motor to operate the thro
ttle in response to ECM control.
Three
sensors (accelerator pedal, mechan
ical guard and the throttle valve) to relay positional information about the
input shaft to the ECM.
R
eturn and control springs fitted to th
e input shaft, mechanical guard, thro ttle valve and dc motor drive gear.
Throttle Cont
rol Modes
There are seven throttle control

modes:
1. 1. Normal
It
em
Par
t Number
De
scription
1—Acce

lerator pedal and mechanic
al guard position sensors
2—Throttl
e (blade)
position sensor
Throttle Body