1998 JAGUAR X308 lock

Engine System - General Infor
mation - Engine
Description an
d Operation

The AJ26 power unit is available in 3.2 L and 4.0 L versions, and comprises:
An eight cylinder 9
0 degree 'V' config
uration liquid cooled aluminium cylinder block incorporating 'Nikasil' plated
cylinder bores.
Pi
stons of open-ended skirt design, with
two compression and one oil control ring.
Two al
uminium cylinder heads, each
incorporating two camshafts.
F
our valves per cylinder.
Al

uminium valve lifters and top mounted shims.
Vari

able valve timing (VVT) of the inlet camshafts (4.0 L normally aspirated only).
Camshaft

covers manufactured from Vinylester.
Al

uminium timing cover which accommodat
es the crankshaft front oil seal.
Sin
gle row primary and secondary chains dr
ive the camshafts of each cylinder bank.
An alu
minium bed pl
ate, incorporating iron main bearing supports, which accomm odate the oil pump pick-up,

diverter val
ve (if fitted) and oil filter.
Main
bearings
which are grooved in the upper positions and plain in
the lower positions. They are manufactured from
aluminium / tin material.
A c
rankshaft with under
cuts and rolled fillets for extra strength.
Fracture
-split connecting rods in sintered-forged steel.
Brackets
bolted to the front of
the cylinder
block are used to mo unt all accessories.
A sin
gle, seven ribbed vee belt
drives the accessories.
An au
tomatic belt tensioner for the front accessory drive,
incorporating a wear indicator.
An advanced en
gine management system inco
rporating electronic throttle control.
The un
it meets the requirements of the CARB OBDII USA legislation.
Ancillary Systems
The an
ci
llary systems, driven by the engine, each have a
detailed Description and Operation along with Diagnostic
Procedures, and Removal and Installation instructions ; refer to the following sections of this manual:
Power Steeri
ng Pump - Section 211-02
Ai
r Conditioning Compressor - Sectio
n 412-03
Engine
C
ooling Pump - Section 303-03
Generator
- Sectio
n 414-02
The drive belt, idler pulley and automatic tensioner are described in Section 303-05.
The engine starting system is described in Section 303-06.
En
gine Management and Emission Control System
Engine Control Modu
le (ECM)
Engine
management and exhaust emissions are controlled by the ECM, which has the
following main functions:
Fu
el injection
Idle
s
peed
Ignition Ev

aporative loss system
Engine
cooling fans Clim
ate control compressor clutch demand
The microprocessor within the ECM receiv es signals from various sensors and other modules and uses a pre-determined
program to compute engine management functions.
Adaptive functions are incorporated in the ECM to cater for co ntinuous adjustments to its computations to suit prevailing
conditions. Because the system also controls emissions to suit all modes, neither CO levels nor idle speed require service
attention or adjustment, except if an error should occur.
On Board Diagnostics are controlled by the ECM with the continuous monitoring of incoming signals and the subsequent
verification against what the module expects to 'see'. Should a si gnal be incorrect or missing, the ECM will substitute a fixed
value to provide the 'limp home mode' and alert the driver of the problem. Fixed values may be adopted for:
Transmission oil
temperature
Mechanica
l
guar
d position
Throttle blade angle Camshaft position

Inta
k
e air temperature
Diagnostic trouble codes (DTC), including OBD II codes, are stored in the ECM memo ry and can be read by an appropriate
retrieval tool.
Should either the ECM or TCM fa il, ensure that the control housing cooling fan is operating correctly. Failure of the cooling
fan MUST be rectified before renewing a control module and details of a fa n failure should accompany a returned control
module.

Speed an
d load
Coo
l
ant temperature
Ti
me el
apsed from start up
Cl
osed l
oop fuelling
Determination of the vapour concentration is made by stepped opening of the EVAP valve and subsequent monitoring of the
fuelling correction. This function is performed prior to purging, so that at the onse t of purging the EVAP valve can be set to
the optimum position. Should the ECM be unable to determine the concentration before purging, a default value is
employed, which is then modified whilst purging is in progress.
When the purging process is operational th e ECM modifies the basic fuelling calculation to maintain the correct air / fuel
ratio.
Purging is inhibited during fuel cut-off and stability / traction control intervention.
Coolant Temperature Sen
sor
Th
e
sensor outputs a voltage to the ECM which decreases as temperature increases.
Cooling Fans


In response to engi
ne coolant temperat
u
re and climate control system demand, the ECM will energize the cooling fans.
Climate Control Compressor
The E
C
M will allow the compressor clutch to be engaged if th
e engine temperature and load demand are normal. Should the
driver require maximum engine powe r or the coolant temperature be high, the request will be denied.
Cranking Signal

The ECM reacts to a signal fr
om th
e Body Processor Module (BPM) when the starter motor relay is energi
zed. This signal is
used to trigger starting, fu el and ignition strategies.
Engine Speed and Cranksh
aft Position
Engine
speed and cran
k position are moni
tored by a sensor which is mounted on the cylinder block (flywheel housing)
behind the crankshaft drive plat e. It indicates rotational speed to the ECM in the form of 12 pulses per crank revolution.
Engine speed is used for synchronization of fuel an d ignition systems, as well as other functions.
Camshaft Position
The ca
mshaft position sensor is mounted at
the rear of Bank 2 cylinder head on the inlet side and provides one signal every
720 degrees of crankshaft rotation. The signal, in conjunction with the signal from the crankshaft position sensor, indicates
to the ECM that the piston of cylinder 1A is approaching TDC on the compression stroke.
Variable Valve
Timing (Where Fitted)
By energi
si
ng a solenoid to allow the pass
age of pressurized oil on each of the inle t camshaft drives, the ECM can vary by a
single stepped amount, the relati ve timing of the inlet valves.
Ign
ition
Ignit
i
on spark is produced by
individual on-plug coil units.
There are two ignition amplifiers; module #1 drives coils 1A, 2B, 3B and 4A, whilst module #2 drives coils 1B, 2A, 3A and
4B. The ECM controls the amplifiers.

Engi
ne -
Torqu
e Specifications


De
s
cription
Nmlb
-
ft
lb
-
in
A
ccessory
drive belt tensioner
43--
A
ccessory
drive belt idler pulley
61--
Air in
ta
ke tube to throttle body
5--
A/C
pipes t
o receiver / drier
9--
A/C pipe m

anifold joints
9--
Camsh

aft bearin
g caps10--
Ca
msh
aft cove
r10--
Ch
arge Air Co
oler Adaptor to cylinder head (SC)
21--
Co
olan
t outlet pipe (AJ26 NA)
10--
Cran
kshaft damper bolt - no lockin
g ring
St
ag
e 1
80--
Stag

e 2
80°--
C
r
ankshaft damper bolt - with locking ring
37
5--
Cra
nkshaft position sensor
10--
Cy
li
nder head bolts M10
35--
Cy
lin
der head bolts M8 (two at front of head)
25--
Driv
es
haft (propshaft) drive flan
ge bo
l
ts
82--
ERG p
i
pe to exhaust manifold
21--
Engi

ne compartment cover (bonnet) hinges
25--
En
gine
coolant radiator top securing panel
25--
E
ng
ine front mounting
70--
En
gine
oil cooler pipes (clamp)
21--
En
gi
ne / Transmission assembly rear mounting centre bolt
35--
En
gi
ne / Transmission assembly rear mounting outer bolts
25--
Ex
ha
ust downpipe support bracket to flywheel housing
50--
Ex
ha
ust downpipe to lower mounting bracket
48--
E
x
haust camshaft sprocket
St
age 120--
Stage 290 °--
Ex
haust manifold to cylinder head
18--
Ex
ha
ust manifold flange to downpipe
18--
E
x
haust Torca clamps
55--
Fuel cross-over elbo

w
10--
Fu
el f
eed pipe to intake manifold
10--
Fuel
Injector (AJ
26)
5--
Fuel
injector ha
rness clips to camshaft cover (SC)
5--
Fu
el p
ressure re
gu
l
ator to intake manifold
10--
F
u
el rail to Char
ge
A
ir Cooler Adaptor (SC)
21--
In
ta
ke manifold to cylinder heads
21--
Inta

ke elbow support brackets
18--
Oil f
i
lter
17--
Oil C
o
oler
7--
P
AS pu
mp hose unions
25--
P
r
imary timing chain fixed guide
12--
P
r
imary timing chain tensioner
12--
Pr

imary timing chain tensioner blade
14--
S
e
condary timing chain tensioner to cylinder
12--
S
t
eerin
g ra
ck45--
Thro
ttle body to intake elbow
21--
Th
ro
ttle cable abutment to throttle body
5--
Th
ro
ttle intake elbow to intake manifold
21--
Ti
mi
ng cover
12--
Variable camshaft t
i
ming oil control unit to intake camshaft
St
ag
e 1
20--
St
ag
e 2
90
°--
Var
iable camshaft timing oil control unit housing (bolt and nut)
21--
Va
ria
ble camshaft timi
ng oil control solenoid
12--
Wa
ter pump pulley
12--

W
ith EM014 disconnected, measure the resistance
between EM014/009 and ground EM016L
1
I
s the resistance < 0.5 OHM?
Yes Reconnect EM014, EM015, PI031 or (PI032)
GO to C10
No Inspect harness / connector EM014, ground stud and
splice EMS037 for corrosion, damage, bent or pushed
back pins and repair as required. Test the system for
normal operation.
C9
: CHECK MECHANICAL CONDITION
R

emove the VVT(s) and ensure
that there is no foreign
matter blocking the oil passageway
1
OK
?
Yes GO to C10
No Rectify as required
C
10: END
Perform

appropriate service drive cycle and check for the
presence of DTC.
1
Has
the fault code cleared?
Yes STOP
No Contact Jaguar Service

1
2.60.48.
12. Install the old bolt which secu red the crankshaft damper, to
allow the crankshaft to be rotated. Use a new bolt on final
installation.
13. The following group of instructions (until stated otherwise)
describe the procedure to rene w the bearing shells in one
connecting rod. Repeat the instructions as necessary.

14
.
Rotate the crankshaft until th e required connecting rod bolts
are accessible.
1. Remove the bolts which secure the bearing cap.
2. Note the position of the identification marks and remove the cap.
Remove the
bearing shell from the cap and note the grade

(colour coded).

15
.
Carefully move the connecting rod and piston assembly
towards the cylinder head to di sconnect it from the crankshaft.
Rotate the crankshaft slightly if necessary.

16
.
Remove the bearing shell from the connecting rod and note
the grade (colour coded). The crankpin grades are also
stamped on the cylinder block.
17. Refer to the Specification Sectio n for details of the crankpin
and bearing shell grades.
18. Clean all components and mating faces.
19. Install and align the new bearing shell to the connecting rod.

Engine - Cr
ankshaft Fron
t Seal4.0L NA V8 - AJ 27/3.2L NA V8 - AJ26
In-v
ehicle Repair
Remov

al
S
pecial Tool(s)

Cr

ankshaft locking, main tool
303-191

Adaptor

303-191-02

Crankshaft front
seal remover
303-541

Crankshaft front seal replacer
3
03-542

Crankshaft pull

ey/damper remover
303-588
1. Open the engine compartment and fit paintwork protection
sheets.
2. Set the engine compartment cover to the service access
position.
3. Remove the drive belt from the fro nt accessory drive. Refer to
Operation 12.10.40.
4. Remove the twin fan and motor assembly for access. Refer to
Operation 26.25.12
5. CAUTION: Under no circumstan ces should the crankshaft
setting peg 303-531 be used in the following operations, to lock
the crankshaft.
• NOTE: Should extra locking of the crankshaft be required, use a
lever against one torque converte r boss. Remove the plastic mesh
cover from the torque converter housing for access.

Instal
l the crankshaft locking tool to the damper.
1. Install adaptor 303-191-02 to the main locking tool 303-191.
2. Reposition the cranks haft/damper to align the
mounting holes and install the locking tool to the
damper using the bolts provided with the tool.
3. Loosen, but do not remove the damper securing bolt
from the crankshaft.
6. Remove the locking tool from the damper.
Remove
the damper securing bolt.

7. NOTE : Th
e damper only needs to be withdrawn along the
crankshaft nose by approximat ely 2mm before removing the
puller. The damper will then either be loose or only require a
sharp tap with a mallet to release it from the split locking ring.
Remove the damper from the crankshaft.
1. Transfer the adaptor 303 -191-02 from the crankshaft
locking tool to the damper extractor tool 303-588
(Use the socket head screws provided with the
puller).
2. Locate the thrust button into the end of the crankshaft; the O-ring holds it in place.
Ass
emble the puller to the damper.
Ex
trac
t the damper from the crankshaft.
8. Remove the puller components from the damper.
Re
move the thrust button from the end of the crankshaft.

9. Re
move the split locking ring from the damper.
10. Remove the internal O-ring seal.