1998 JAGUAR X308 egr

T
he cooling system for the supercharged engine is very similar
to the normally aspirated engine, but with the addition of a
water cooled, intake air charge cooling system. This comprises a radiator, an electrically operated water pump and two
charge air cooler assemblies (heat exchangers) - one for each bank. The system works independently, but is connected to the
main cooling system at the bottom hose to allow for therma l expansion and to help to prevent unwanted circulation.
The condenser for the air conditioning system fits between th e coolant main radiator and the charge air cooling system
radiator.
Cylinder Block Heater, Drain Location
ItemDe
scription
1Rad

iator - Intake Air Coolant
2Ele

ctrically Operated Coolant Pump
3Top Hose
4Charge Air Coo

lers -
Intake Air Cooling
5Fi
lling Point for Intake Air Cooling
6N

on-Return Valves - Heater
7Ele

ctrically Operated Coolant Pump
8Hea

ter Matrix
9Wate

r Valve - Heater Control
10EGR V

alve (when fitted)
11Thr

ottle Body
12Coolan

t Recovery Bottle
13H

eader/Expansion Tank
14Eng

ine Coolant Pump
15The

rmostat Housing
16Bottom

Hose
17Air Bleed

Pipes
18Rad

iator - Main Cooling System

The cooling
pack incorporates the radiator a
ssembly with integral transmission oil cool er (located in the radiator outlet tank),
an air conditioning condenser, and the cooling fans and cowl assembly.
The cooling pack on supercharged vehicles is the same as described above, but with the addition of a charge air cooler
coolant radiator located in front of the condenser.
Radiator Mounti
ng/Retention
T
he radiator is mounted on four rubber mounts, one on each
end of the upper and lower horizontal face. The two lower
mountings are supported on two isolated brackets mounted on the body; the lower cradle assembly has subsequently been
deleted.
A closing panel made from polypropylene, which retains the radiat or assembly, fits over the top of the radiator and is bolted
to the vehicle top panel.
Coolant Hoses - Engine

Whe r
e considered necessary, some hose conn
ections have an indication mark to ensure correct orientation of the hose when
being fitted.
All joints use spring-band clips, except small pipes on the bleed system joints - which use cobra clips. The heater feed and
return hoses use quick-connection unions.
Supply and return hoses for the heater are located between the cylinder banks.
A connection on the rear of the A-bank provides coolant supply for the electronic throttle and the EGR valve (where fitted).
The outlet from the electronic throttle connects to the return hose from the heater.
Cool
ant Header and Recovery Tanks
A recovery system comp
rising the header tank
and a recovery tank is fitted. The recove ry tank is located in front of the left
hand front wheel arch liner.
The header tank provides the cooling system filling point and carries the coolant level sensor. The pressure cap allows
controlled release of coolant to the re covery tank during normal operation.
The recovery tank accommodates the expansion of the system coolant during normal operation. On engine cool-down, the
coolant contracts and is returned to the main system.
Coo lin
g Fans
The two
rad
iator cooling fans are mounted in
a cowl assembly within the cooling module.
The fans are controlled by the ECM dependent on the demand fr om the cooling system (temperature) or the air conditioning
ItemDescrip
tion
1EGR
E
ngines
2Non
-
EGR Engines
3Hea
ter Connections

Conne
ct the scan tool
1
Have the DTC(s) and fr

eeze
frame data been recorded?
Yes GO to D2
D
2: CHECK FUSE
•

NOTE: See further steps for poss
ible cause of fuse failure.
Chec
k fuse F2 integrity (located in the engine
management fuse box).
1
OK
?
Yes GO to D3
No Renew fuse and test the syst em for normal operation.
D3: C
HECK RELAY SOCKET SUPPLY VOLTAGE
•

NOTE: Do not replace relay.

Fuel D
istribution
Fuel is supplied to th
e engine
via eight fuel injectors (one pe r cylinder). The injectors are located in two fuel rails which r un
the length of each cylinder bank and ar e integral with the air intake manifold.
Fuel pumped from the tank enters a feed pipe at the rear of bank 2. Fuel flow is along bank 2 fuel rail, across the top front
of the engine (cross-over pipe) and through bank 1 fuel rail, the unused fuel re turning to the tank via a pressure regulator.
The fuel injectors are each controlled electrically from the engine control module (ECM).
A test valve is fitted to the cross-over pipe connecting the fu el rails at the front of the intake manifold. This valve allows the
fuel system to be depr essurized during servicin g and troubleshooting.
Fuel Injector

Eight, side-fed, dual straight-jet fuel injectors are fi tted in the fuel rails.
The injector consists of a solenoid, core, needle valve and ho using. When a control signal from the ECM is applied to the
solenoid coil, the needle valve lifts up and fuel is injected under pressure into the intake port. The fuel sprays from the
injectors are directed onto the back of the intake valves.
The injection quantity is determined by the length of time that the ECM signal is applied to the solenoid coil.
The injectors installed in the fuel rails of supercharged engines are of a higher flow rating than those installed in normally
aspirated engines and are secured in position by spring clips. Seals are instal led between the injector mounts of the fuel
rails and the related re cesses in the charge air cooler adaptors.
Pressure Regulator

(ECT) se
nsor
Blocked part-load breather
(s
ervice action S474)
Injec
t
or leak
Engine stalls
soon
after start
F
u
el pump relay
ECM relay Thr
o
ttle contaminated
CMP/CKP sen
s
or
synchronization malfunction
Harness Fuel
pump
MAF
s
ensor malfunction
Engine coolan
t
temperature
(ECT) sensor
Fue l
lines
Air leakage Fu

el pressure regulator
F
o
r fuel pump relay tests,
GO to Pinpoint Test E.
.
F or ECM
relay tests,
REFER to Section 303
-14 Elec tronic En
gine
Controls.
Check bull etins for throttl
e cleaning procedure. For

CMP/CKP sensor tests,
REFER to Section 303
-14 Elec tronic En
gine
Controls.
Chec k fu
el pressure,
REFER to Section 310
-00 Fu
el System
- Ge
n
eral
Informati
o
n
.
F or MAF sensor and
ECT sensor tests,
REFER to Section 303
-14 Electronic En
gine
Controls.
For fuel l
ine information,
REFER to Section 310
-01
Fuel Tank and Lines
.
F or i
ntake system information,
REFER to Section 303
-1 2
Intake Air Distribution
and F
ilt
ering
.
F o
r fuel pressure regulato
r check, GO to Pinpoint
Test D.
.
Engine h e
sitates/poor
acceleration
Fue l
pump
Exhaus
t gas
recirculation
(EGR)
Air leakage Stop lamp swi t
ch
Throttl
e
sensors
Throttl
e
motor
Spark plugs

fouled
Check f
o
r water ingress into
spark plug wells
Ignition coil fail
ure(s)
HT sho
rt to ground (tracking)
check rubber
boots for
cracks/damage
ECM failu r
e
Chec
k fu
el pressure,
REFER to Section 310
-00 Fu
el System
- Ge
n
eral
Informati
o
n
.
F o
r EGR information,
REFER to Section 303
-08 En gin
e Emission
Control.
F or i
ntake system information,
REFER to Section 303
-1 2
Intake Air Distribution
and F
ilt
ering
.
F or stop l
amp switch in
formation, refer to the
wiring diagrams. For throttle position sensor and throttle motor relay tests,
REFER to Section 303
-14 Elec tronic En
gine
Controls.
For ign i
tion system,
REFER to Section 303
-07 En
gine Ignition
.
Contact dealer techn i
cal
support for advice on
possible ECM failure.
Engine ba ckfiresFuel
pump
Air leakage MAF s
e
nsor
HO2 sensors Spark plugs
Check fo
r water ingress into
spark plug wells
HT short to ground (tracking) check rubber
boots for
cracks/damage
Ignition coil fail
ure(s)
Chec
k fu
el pressure,
REFER to Section 310
-00 Fu
el System
- Ge
n
eral
Informati
o
n
.
F or i
ntake system information,
REFER to Section 303
-1 2
Intake Air Distribution
and F
ilt
ering
.
For MAF and HO2
sensor circuit tests,
REFER to Section 303
-14 Electronic En
gine
Controls.
For igni
tion system,
REFER to Section 303
-07 En
gine Ignition
.
Engine
s
urges
Air leakage Fue
l
pump
Stop lamp swi
t
ch
MAF s
e
nsor
Harness Throttl
e
sensors
Throttl
e
motor
Spark plugs
Check fo
r water ingress into
spark plug wells
HT sho rt to ground (tracking)
check rubber
boots for
cracks/damage
ECM failu r
e
F
or i
ntake system information,
REFER to Section 303
-1 2
Intake Air Distribution
and F
ilt
ering
.
Chec k fu
el pressure,
REFER to Section 310
-00 Fu
el System
- Gen
e
ral
Informati
o
n
.
F or stop l
amp switch in
formation, refer to the
wiring diagrams. For MAF se nsor, throttle position
sensor and throttle motor relay tests,
REFER to Section 303
-14 Elec tronic En
gine
Controls.
For ign i
tion system,
REFER to Section 303
-07 En
gine Ignition
.
Contact dealer techn i
cal
support for advice on
possible ECM failure.

Fuel Char
ging and Controls - Fu
el Injectors4.0L SC V8 - AJ26
Remo
val and Installation
Remov
a
l
Installation
1. Disc onne
ct battery ground cable (IMPORTANT, see SRO
86.15.19 for further information).
2. WARNING: BEFORE PROCEEDING, IT IS ESSENTIAL THAT
THE WARNING NOTES GIVEN IN SECTION 100-00 (UNDER THE
HEADING 'SAFETY PRECAUTIONS') ARE READ AND
UNDERSTOOD.
Depressurize fuel syst em; refer to 19.50.02.
3. Drain radiator coolant; refer to 2
6.10.01.
4. Remove air cleaner cover / inta ke assembly; refer 19.10.30.
5. Remove throttle body; refer to 19.70.04.
6. Remove throttle induction elbo w; refer to (SC) 19.70.28.
7. Remove exhaust gas re-circulation valve (EGR) if fitted; refer
to 17.45.01.
8. Remove supercharger outlet duct and gasket; refer to
18.50.16.
9. Remove coolant outlet pipe; refer to (SC) 26.31.08 .
10. Remove supercharger drive belt; refer to 18.50.08.
11. Remove supercharger assembly; refer to 18.50.15.
12. Remove bank 1 or 2 charge air cooler as required; refer to
18.50.18 and / or 18.50.19.

13 . Di
sconnect fuel injector harness.
1. Disconnect injector connectors.
2. Loosen two nuts which se cure harness to camshaft
cover.
3. Reposition harness to al low access to injectors.

14. CAUTI
ON: Take care to avoi
d dropping any objects or
foreign matter into induction ma nifold with the fuel injectors
removed.
Remove fuel injector(s). 1. Prise out injector retaining clip, ensuring that it is not
ejected and lost. Note orientation of the clip.
2. Using a suitable implemen t, carefully lever injector
from fuel rail.
3. Discard injector O-rings.
15 . Cle
an all mating faces.

1.
Install
fuel injector(s).
1. Install new O-rings, lubricated with petroleum jelly, to
fuel injector.
2. Install fuel in jector into fuel rail. Press firmly until it is
felt to click into place.
3. Hold injector firmly down and fit injector securing clip
in the correct orientation.

2. Conne
ct fuel injector harness.
1. Reposition harness.
2. Tighten nuts which secure harness to camshaft cover.
3. Re-connect injectors.
3. Install charge air c ooler; refer to 18.50.18 and / or 18.50.19.
4. Install supercharger asse mbly; refer to 18.50.15.
5. Install supercharger driv e belt; refer to 18.50.08.
6. Install coolant outlet pi pe; refer to 26.31.08.
7. Install throttle induction elbow; refer to 19.70.28.
8. Install exhaust gas re-circulation valve (EGR) if applicable;
refer to 17.45.01.
9. Install throttle body ; refer to 19.70.04.
10. Install supercharger outlet duct; refer to 18.50.16.
11. Install air cleaner cover / intake assembly; re fer to 19.10.30.
12. Refill cooling system; refer to (SC) 26.10.01 .
13. Reconnect battery ground cable (IMPORTANT, see SRO
86.15.15 for further information).