air control JAGUAR X308 1998 2.G Repair Manual

Driver Informa
tion Chart
•
NOTE: Use this table to identify DTCs associated with the me
ssage center display, then refer to the DTC index for possible
sources and actions.
• NOTE: For definitions of Default Modes, see the foot of this table.
Engine deton
ates/knocks
Fue
l pump
HO2 sensors Air leakage Blocked part-load breather
(
service action S474)
Mass ai

r flow (MAF) sensor
Chec
k fuel pressure.
REFER to Section 310
-00
Fuel System
- Gen
eral
Informati

on
.
F
or HO2 sensor circuit
tests, check for DTC
indicating which sensor and follow indicated
pinpoint test. For intake system information,
REFER to Section 303
-1
2 Intake Air Distribution
and F

iltering
.
Check service
action S474. For MAF sensor circuit
tests,
REFER to Section 303
-14 Elec
tronic Engine
Controls.
No

throttle response
Throttl
e sensors
Throttl

e motor
F
or throttle position se
nsor and throttle motor
relay tests,
REFER to Section 303
-14 Elec
tronic Engine
Controls.
Poor throttle responseThrottl

e sensors
Throttl

e motor
Air leakage Mass ai

r flow (MAF) sensor
F
or throttle position se
nsor and throttle motor
relay tests,
REFER to Section 303
-14 Elec
tronic Engine
Controls.
Fo
r intake system,
REFER to Section 303
-1
2 Intake Air Distribution
and F

iltering
.
For MAF
sensor tests,
REFER to Section 303
-14 Elec
tronic Engine
Controls.
Warning
lightMess
age
De
fault Mode
DT
C
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1224
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1229
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P01
22, P0123,
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P02
22, P0223
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P0121
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P11
22, P1123
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P12
22, P1223
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P11
21, P1632
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P12
51, P0560, P1658
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1631
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1611
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1633
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P1609
Re

d
Engine
Failsafe
Mode
Lim
p-Home
P05
06, P0507
Re

d
Engine
Failsafe
Lim
p-Home
P1656

Default mode Definitions

MECH
ANICAL LIMP-HOME MODE:

No el
ectronic throttle operation (mechanical
operation for last quarter of pedal travel)
M
aximum 25° throttle opening,
depending on adjustment of th rottle mechanical linkage
Engine
speed restricted to 3000
rpm maximum, by fuel cut-off
Hi
gh idle speed (1200 rpm approx.)
Misfire

at idle, due to cylinder cut as a means of control
ling idle speed (the misfire will switch cylinders, as the
strategy varies th e cylinder cut)
Cruise (speed) contr
ol inhibited
REVERSE THROTTLE PROGRESSION ENABLED:
El
ectronic throttle operation, limited to maximum 25°
Cruise (speed) contr

ol inhibited
• NOTE: The throttle oper ation uses the same map as for reverse gear.
ENGINE SPEED LIMIT:
Engine
runs normally, up to 3000 rpm
Engine

speed restricted to 3000
rpm maximum, by fuel cut-off
Cruise (speed) contr
ol inhibited
LIMP-HOME UNAVAILABLE:
Cruise (speed) contr
ol inhibited
R

everse throttle pr
ogression engaged at second occurrence of DTC flagging
Diagnostic Trouble Code (D
TC) index
DT
C
Cond
ition
P
ossible Causes
Acti
on
P0171Right-hand cylinders combustion too

leanAir
intake leak between MAF
sensor and throttle
F
uel filter system blockage
F

uel injector blockage
F

uel pressure regulator failure (low

fuel pressure)
Low f
uel pump output
H0

2S harness wiring fault
E

xhaust leak (before catalyst)
ECM receivi

ng incorrect signal from

one or more of the following
sensors - ECT, MAF, IAT, TP.
Fo
r intake system,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
F
or fuel filter,
REFER to Section 310
-01
Fuel Tank
and Lines.
Chec
k the fuel injectors. Check the
fuel pressure regu lator. Check fuel
pressure. For HO2S circuit tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
F
or exhaust information,
REFER to Section 309
-00
Exhaust
Sy

stem
.
For se
nsor circuit tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
P0172Right-hand cylinders combustion too

ri
ch
Engine
misfire
Bl

ocked air filter
F

uel system return blockage
Leak

ing fuel injector(s)
F

uel pressure regulator failure
(high fuel pressure)
ECM receivi
ng incorrect signal from

one or more of the following sensors - ECT, MAF, IAT, TP
Chec
k for 'engine misfire detected'
DTCs. Check the air filter element,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
Chec
k the fuel lines,
REFER to Section 310
-01
Fuel Tank
and Lines.
Chec
k the fuel injectors,
REFER to Fuel Injectors
- in t
his
section.
For fuel pressure regulator check,GO
to Pinpoint Test D.
.
Check the fuel
pressure,

Ignition coil
failure(s)
HT sho

rt to ground (tracking)
check rubber boots for cracks/damage
Spark plug
failure/fouled/incorrect
gap
Cy
linder compression low
F

uel delivery pressure (low/high)
F

uel injectors restricted/leaking
Fuel contamination


P

AS pulley bolts loose (see Service

Action S462)
W
orn camshaft/broken valve
springs
P
inpoint Test
A.
.
Check fuel
pressure,
REFER to Section 310
-00
Fuel
Sy

stem
- General
Information
.
Chec
k fuel injectors,
REFER to Fuel Injectors
- in t
his
section.
Check service actions.
P0301Misfire
detected, Cyl 1
R
EFER to possible sources for P0300
R
EFER to actions for P0300.
P0302Misfire

detected, Cyl 3
P0303Misfire

detected, Cyl 5
P0304Misfire

detected, Cyl 7
P0305Misfire

detected, Cyl 2
P0306Misfire

detected, Cyl 4
P0307Misfire

detected, Cyl 6
P0308Misfire

detected, Cyl 8
P0460F

uel level sense signal performance
Fue
l level sensor
to instrument
cluster circuits in termittent short
or open circuit
F
uel level sensor failure
Instrument cluster
faul
t (incorrect
fuel level data)
F
or fuel level sensor tests,GO to
Pinpoint Test B.
.
P1224Throttl
e control position error
Thro
ttle adaptations not performed

after battery disconnect
TP se
nsor disconnected
TP se

nsor to ECM sense circuits;
open circuit, hi gh resistance
Throttl
e motor relay failure
Th

rottle motor relay to ECM circuit

fault
Throttl
e motor relay power supply
open circuit
ECM ground circuit faul
t (relay coil
drive)
Throttl
e motor to ECM drive
circuits; open circuit, short circuit, high resistance
Throttl
e motor failure
Throttl

e body failure
Carry
out the throttle adaptation
procedure,
REFER to Section 303
-14
Electronic
Engine

Controls
.
ECM adaptations. For
throttle motor
relay tests, throttle position sensor tests, ECM ground tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
P1229Throttl

e motor control circuit
malfunction
Throttl
e motor disconnected
Throttl

e motor to ECM drive
circuits; short circuit or open circuit
Throttl
e motor failure
Fo
r throttle moto
r relay tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
P1250Engine

load malfunction
Air
intake leak
Engine

breather leak
TP se

nsor circuit fault (DTC P0121)

Throttl
e valve spring failure
F
or air intake system,
REFER to Section 303
-12
Intake Air

Distribu
tion and Filtering
.
Chec
k engine breather system for
leaks. For TP sensor tests,
REFER to Section 303
-14
Electronic
Engine

Controls
.
P1313Right-hand cylinders misfire rate
cat
alyst damage (this DTC will flag
only when accompanied by an
individual cylinder misfire DTC: P0300-P0308)
R
efer to possible causes for P0300-P0308
R
efer to actions for P0300-P0308.
P1314L

eft-hand cylinders misfire rate
catalyst damage (this DTC will flag only when accompanied by an
individual cylinder misfire DTC: P0300-P0308)
R
efer to possible causes for P0300-P0308
R
efer to actions for P0300-P0308.

ci
rcuit includes the EMS fuse box,
fuse 05, and the fuel injection relay. For additional information,
refer to the wiring diagrams. CLEAR DTC. TEST the system for normal operation.
A4: CHECK
THE INJECTOR GROUND
CIRCUIT FOR HIGH RESISTANCE
Turn the ignition swi
tch to the OFF
position.
1
Di
sconnect the battery negative terminal.
2
D

isconnect the ECM electrical connector, (EM15, vehi
cles with AJ26 engine, EM84, vehicles with AJ27
engine).
3
Meas
ure the resistance between the relevant injector harness electrical connector (IJ03 to IJ10,
vehicles with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and the ECM electrical
connector, pins as follows -
Vehicles with AJ26 engine:
Cy
l 1 IJ03, pin 01 (BU) and EM15, pin 07
Cy

l 2 IJ07, pin 01 (BU) and EM15, pin 18
Cy

l 3 IJ04, pin 01 (BN) and EM15, pin 17
Cy

l 4 IJ08, pin 01 (BN) and EM15, pin 05
Cy

l 5 IJ05, pin 01 (BG) and EM15, pin 16
Cy

l 6 IJ09, pin 01 (BG) and EM15, pin 04
Cy

l 7 IJ06, pin 01 (BW) and EM15, pin 06
Cy

l 8 IJ10, pin 01 (BW) and EM15, pin 15
Vehicles with AJ27 engine:
Cy
l 1 PI07, pin 01 (B
G) and EM84, pin 02
Cy
l 2 PI11, pin 01 (BW) and EM84, pin 06
Cy

l 3 PI08, pin 01 (BO) and EM84, pin 21
Cy

l 4 PI12, pin 01 (BW) and EM84, pin 04
Cy

l 5 PI09, pin 01 (B
G) and EM84, pin 14
Cy
l 6 PI13, pin 01 (BO) and EM84, pin 03
Cy

l 7 PI10, pin 01 (BW) and EM84, pin 05
Cy

l 8 PI14, pin 01 (BR) and EM84, pin 13
4
Is th

e resistance greater than 5 ohms?
Yes REPAIR the circuit between the relevant injector harness electrical connector pin 01 and the engine
control module electrical connecto r. For additional information, refer to the wiring diagrams. CLEAR
the DTC. TEST the system for normal operation.
No GO to A5
.
A5: CHECK
THE INJECTOR GROUND CI
RCUIT FOR SHORT CIRCUIT TO BATTERY
R
econnect the battery negative terminal.
1
Meas

ure the voltage between the relevant injector harness electrical connector (IJ03 to IJ10, vehicles

with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and GROUND.
2
Is th
e voltage greater than 3 volts?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No GO to A6
.
A6: CHECK
THE INJECTOR GROUND CI
RCUIT FOR SHORT CIRCUIT TO GROUND
Meas
ure the resistance between the relevant injector harness electrical connector (IJ03 to IJ10,
vehicles with AJ26 engine, PI07 to PI14, vehicles with AJ27 engine), pin 01 and GROUND.
1
Is
the resistance less than 10,000 ohms?
Yes REPAIR the short circuit. For addi tional information, refer to the wiring diagrams. CLEAR the DTC.
TEST the system for normal operation.
No Contact dealer technical support for advice on possible ECM failure.
P
INPOINT TEST B : DTC P0460; FUEL
LEVEL SENSE SIGNAL PERFORMANCE
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
B1: CHECK

THE FUEL LEVEL SENSOR REFERENCE GROUND
Di

sconnect the fuel level sensor electrical connector, BT15.
1

Fuel Char
ging and Controls - Fu
el Injection Supply Manifold LH
Remo
val and Installation
Remov
a
l
Installation
1. Re
move fuel injectors; refer to (SC) 18.10.01.

2. Disc
onnect fuel feed
pipe from fuel rail.
1. Remove two bolts.
2. Reposition fuel feed pipe.
3. Discard O-ring.

3. Re
move fuel rail from charge air cooler adaptor.
1. Remove three bolts.
2. Reposition fuel rail and remove cross-over pipe securing bolt.
Di
scard O-ring from fuel cross-over pipe.
R
e
move fuel rail.

4. Re
move seals between fuel rail
and charge air cooler adaptor.
1. Discard seals.
2. Clean and inspect mating faces.
1. Install new seals between fuel rail and charge air cooler
adapter ensuring that they are fully seated.
2. Install fuel rail to fuel cross-over pipe.
Inst al
l new O-ring and lubricate with petroleum jelly.
1. Install bolt.

Fuel Char
ging and Controls - Fu
el Injection Supply Manifold RH
Remo
val and Installation
Remov
a
l
1.
Re
move fuel injectors; refer to (SC) 18.10.01.

2. Disc
onnect fuel pressure regulator.
1. Remove bolts.
2. Reposition pres sure regulator.
Disc
ard O-ring.

3. Re
move fuel rail from charge air cooler adaptor.
1. Remove three bolts.
2. Remove fuel rail; still co nnected to fuel crossover pipe
and fuel return pipe.

4. Re
move fuel rail from fuel cross-over pipe.
1. Remove bolt.
2. Discard O-ring.

5. Re
move fuel rail to charge air cooler adaptor seals.
1. Discard seals.
2. Clean and inspect mating faces.

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.

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

F
our separate ignition coils are mounte
d to each camshaft cover, directly above the spark plugs and are controlled
by the ECM via the ignition control modules.
Each
coil comprises an encapsulated step-up transformer
and a direct push on connection to the spark plug.
Spa
rk Plug
The spark plu
g changes the high voltage pulse into a spark whic
h ignites the fuel and air mixture. Refer to specification in
this section for spark plug details co vering different markets and models.
Igni
tion Coil - coil on plug

Engine Igni
tion -
Engine Ignition
D
iagnosis and Testing
I

nspection and Verification
1.
1. Veri
fy the customer concern.
2. 2. Confirm which, if any, warning li ghts and/or messages were displayed on the instrument cluster.
• NOTE: If any warning lights and/or me ssages were displayed when the fault occurred, refer to the Driver Information
table for DTCs associated with the display, then to the DTC index table for possible sources and actions. Some warnings will
appear to clear when the ignition is cycl ed. This is often because the warning has flagged as a resu lt of one of the vehicle's
on-board diagnostic routines having run to detect the fault. If the same routine is not run when the ignition is switched ON,
the warning will not reflag until the routine does run. See the DTC summaries for drive cycle routines.
3. 3. Visually inspect for obvious signs of mechanical or electrical damage.
V
isual Inspection Chart
4.
4. Veri
fy the following syst
ems are working correctly:
Air in
take system
Coo

ling system
Charging system


F

uel charging system
5. 5. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding
to the next step.
6. 6. Where the Jaguar approved diagnostic sy stem is available, complete the S93 report before clearing any or all fault
codes from the vehicle.
• NOTE: If a DTC cannot be cleared, then there is a permanent fault present that flag s again as soon as it is cleared (the
exception to this is P1260, which will only clear following an ignition OFF/ON cycle after rectification).
7. 7. If the cause is not visually evident and the Jaguar approv ed diagnostic system is not available, use a fault code
reader to retrieve the fault codes be fore proceeding to the Diagnostic Trou ble Code (DTC) Index Chart, or the
Symptom Chart if no DTCs are set.
• NOTE: If the DTC flagged was not present for two or more co nsecutive cycles, it is classed as temporary, and will be
deleted following three cycl es during which no fault was present. This could result in a reported wa rning light/message with
no stored DTCs. If a fault is present for three consecutive cycles, the DTC becomes permanent, and will remain in the
module's memory for 40 drive cycles (a cy cle is an ignition ON/OFF, which will occur during the owner's normal use of the
vehicle. No action on the part of the technician is necessary to perform this cycle. A drive cycle is a series of conditions
needed to make the on-board diagnostic ro utine run, and may need a specific action on the part of the technician. See the
DTC summaries for driv e cycle routines).
8. 8. Using the Jaguar approved diagnostic system where available, and a scan tool where not, check the freeze frame
data for information on the conditions applicable when the fault was flagged. The format of this will vary,
depending on the tool used, but can pr ovide information useful to the technician in diagnosing the fault.
CAUTION: When probing connectors to take measurements in the course of the pinpoint tests, use the adaptor kit,
part number 3548-1358-00.
MechanicalElectrical
Engi
ne oil level
Coo

ling system coolant
level
Fuel contamination

Throttle body Poly

-vee belt
F
uses
W

iring harness
E

lectrical connector(s)
Sens

or(s)
Engine

control module (ECM)
Relay date codes.

If the date on the relay is between R6 k1 and R6 k8, replace
the relay