1998 JAGUAR X308 cooling system

to th
e throttle body.

51 . Co
nnect the intake tube to the throttle body.
1. Fit a new seal and connect the intake tube to the throttle body.
2. Fit the two bolts which secure the intake tube to the throttle body.

52 . Conne
ct the air cleaner cover.
F
it
the five clips which secu
re the air cleaner cover.

53 . Re
connect the breather pipe to the A-Bank camshaft cover.
1. Fit a new O-ring seal to the breather pipe.
2. Connect the breather pipe to the stub pipe.
54. Connect the air flow meter connector.
55. Fit a new Ty-strap to secures the vacuum pipe to the
induction elbow.
56. Refill the cooling system. Refer to Operation 26.10.01.
57. NOTE: When the engine is star ted from cold and run for a
short period only, before being swit ched off, a quantity of oil will

Engine Cooling
- Engine Cooling
Descr
i
ption and Operation
Engine Cooling Comp onents - Normally Aspirated Vehicles

Engine cooling is via a low volume, high velocity system which achieves a very fast warm up. The temperature of the
combustion chambers is reduced along with a more even temperature distribution. The temperature of the bores is increased.

F r
om the pump, coolant flows into each bank of the cylinder bl
ock. In each bank, approximately 50% of the coolant cools the
cylinder bores and the remainder is diverted th rough the bypass gallery to the cylinder head.
With the thermostat closed, coolant returns directly to the pump through the bypass on the thermostat housing.
With the thermostat open, coolant returns to the pump via the radiator.
The cooling system uses a mixture of water and Jaguar Anti-Freeze/Inhibitor (Dow 542).
The cooling system on a supercharged engine is similar, but has additional components for cooling the intake air.
Engine Cooling Co mponents - Supercharged Vehicles
ItemDescrip
tion
1Thr
ottle B
ody
2Hea
ter Return
3Coolant Pum p
4Ther
mostat Housing
5Vehicle Radia
t
or
6Hea
ter Su
pply
7Bleed
Outl
et (to expansion tank)
8EGR V
a
lve (when fitted)
9Bleed
Outl
et (to expansion tank)

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

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

Engine Cooling - Engine Cooling
Diagn
osis and Testing
Related Faults / Codes

Adaptive
Fue
ling
Sym
p
tom Chart
Sy
m
ptom Chart
S
p
ecial Tool(s)

D
i
gital multimeter

Generi
c scan tool
Conditi
on
Possib
l
e Source
Acti
o
n
D
T
C P0171 System too lean bank
1 (A)
D T
C P0174 System too lean bank
2 (B)
Fuel delivery blockage Fu
el delivery pressure (low)
F
a
ulty injector (blocked)
Ai
r i
ntake system leak
F
u
el injector electrical fault
ECT sensor
faul
t
MAFM sensor fault IAT se
nsor fault

Thro
tt
le position sensor
fault
Mec hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Go t
o DTC P020
1 to 0208
Go t
o
DTC P0116 to 0118, P0125
Go t
o
DTC P0101 to 0103, P1104
Go t
o DTC P011
1 to 0113
Go t
o
DTC P0121 to 0123, P0222,
P0223
D T
C P0172 System too rich bank
1 (A)
D T
C P0175 System too rich bank
2 (B)
F u
el delivery pressure
(high)
F a
ulty injector (leaking)
F
u
el injector continuously
open
Ai r i
ntake system restricted

Fu
el injector electrical fault
ECT sensor
faul
t
MAFM sensor fault IAT sensor fault


Thrott

le position sensor
fault
Mec hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Mec
hanica
l check
Go t
o DTC P020
1 to P0208
Go t
o
DTC P0116 to P0118, P0125
Go t
o
DTC P0101 to P0103, P1104
Go t
o DTC P011
1 to P0113
Go t
o
DTC P0121 to P0123, P0222,
P0223
Sy m
ptom
Possib
l
e Sources
Acti
o
n
D
T
C P0116 ECT circuit range / performance problem
Thermostat
Coo
l
ant level / contamination
Sensor out of range
Harness open circuit
Connector loose or corroded
*
*
*
*
*
GO to Pinpoint

Test A

*
D
T
C P0125 Insufficient coolant temperature for closed
loop fuel control
Thermostat
Coo l
ant level / contamination
Sensor out of range
Harness open circuit
Connector loose or corroded
*
*
*
*
*
GO to Pinpoint

Test A

*
D
T
C P0117 ECT circuit low input
Sensor o
p
en circuit
Harness open circuit
Harness short
*
*
*
GO to Pinpoint

Test B

*

Engine Cooling - Cooling System Draining,
Filling and Bleeding4.0L NA V8
- AJ27/3.2L NA V8 - AJ26
Gen
eral Procedures
Drain
Refill
1. O
pen the engine compartment and fit paintwork protection
sheets.
2. Ensure that the cooling system is cool and very carefully,
remove the pressure cap from the header tank.
3. Raise the vehicle.

4. Drain th
e coolant.
Pla

ce a coolant drain tray on
the floor, below the radiator
drain plug.
1. Remove the radiator drain plug. and allow the coolant to drain.

5. Fit a new seal to the
drain plug.
1. Remove the seal from the drain plug. and clean the plug face.
Fit a new seal.

6. Re
fit the radiator drain plug.
Cl

ean any coolant from the
underside of the vehicle.
Remove the drain tray.
7. Lower the vehicle.
1. Refill the cooling system with a 50% solution of water and
Jaguar Antifreeze / Corrosion Inhibitor ESD-M97B49-A.
1. Fill the cooling system at the header tank until the level stabilises at the top of the breather neck.

Allow at least 2 minutes f
or ai
r to purge from the system.
Top up the he
ader tank as re
quired and fit the pressure
cap.
2. Switch on the ignition, switch off the climate control system
and start the engine.
3. Run the engine at between 1500 and 2000 rpm until the
cooling fans operate.
4. Switch on the A/C system, set to maximum heat, and check
that heat is coming from the heat er at the fascia vents or the
footwell outlets.
5. Switch off the engine and allow it to cool down.
6. When cool, remove the pressure cap and top up the system as
necessary at the header tank.

7. If n e
cessary, fit new seals to the pressure cap.
1. Remove both O-rings from the pressure cap.
Fit and
fully seat new O-rings to the pressure cap.
8. Fit the pressure cap.
9. Remove the paintwork protection sheets and close the engine
cover.

Engine Cooling - Cooling System Draining, Filling and Bleeding4.0L SC V8 -
AJ26

Gen
eral Procedures
Drain
Refill
1. O
pen the engine compartment and fit paintwork protection
sheets.
2. Ensure that the cooling system is cool and very carefully,
remove the pressure cap from the header tank.
3. Raise the vehicle.

4. Drain th
e coolant.
Pla

ce a coolant drain tray on
the floor, below the radiator
drain plug.
1. Remove the radiator drain plug. and allow the coolant to drain.

5. Fit a new seal to the
drain plug.
1. Remove the seal from the drain plug. and clean the plug face.
Fit a new seal.

6. Re
fit the radiator drain plug.
Cl

ean any coolant from the
underside of the vehicle.
Remove the drain tray.
7. Lower the vehicle.
1. Refill the cooling system with a 50% solution of water and
Jaguar Antifreeze / Corrosion Inhibitor ESD-M97B49-A.
1. Remove the threaded plug and Dowty washer from the charge air cooler fill point.