1998 JAGUAR X308 exhaust

Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to F2
F2: CHECK FOR LOW EXHAUST TEMPERATURE
Check the engine and exhaust system for normal running
temperature 1
Is the engine and exhaust sy stem up to normal running
temperature?
Yes GO to F3
No Rectify possible leaking exhaust manifold / catalyst,
general causes of an over ri ch mixture and engine cooling
system operation. Test the sy stem for correct operation.
GO to F8
F3: CHECK FOR O2 SENSOR HEATER CONTINUITY
Ignition switch to position 0 1
Disconnect EM023
Bracket on top of gearbox or Bulkhead rear of engine
2
Measure the resistance between EM023/001 and
EM023/002. 3
Is the resistance between 4 and 10 OHM?
Yes
GO to F4
No Renew O2 sensor. Reconnect plug(s).
GO to F8
F4: CHECK FOR O2 SENSOR FAILURE

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

eeze
frame data been recorded?
Yes GO to H2
H2: CHECK
FOR LOW EXHAUST TEMPERATURE
Chec

k the engine and exhaust
system for correct operation
and normal running temperature
1
Is th
e engine and exhaust system operating correctly and up to
normal running temperature?
Yes GO to H3
No Rectify leaking exhaust manifold / catalyst, general causes of
an over rich mixture and engine cooling system operation and
test the system for correct operation.
GO to H7
H
3: CHECK FOR O2 SENSOR FAILURE
I

gnition switch to position 0
1
Di

sconnect EM024
Bracket on top o

f gearbox or
Bulkhead rear of engine
2
R
un the engine for a period to
warm the sensor and then
maintain a steady speed of approximately 2500 rpm.
3
W
ith EM024 disconnected, measure the voltage between
EM024/001 and EM024/002.
4
Is
the voltage between 600mV and 1.0 Volt?
Yes GO to H4
No Renew O2 sensor. Reconnect plug(s).
GO to H7
H
4: CHECK FOR O2 SENSOR FAILURE

Exha
ust System - Catalyti
c Converter LH4.0L NA V8 - AJ27/3.2L NA V8 -
AJ26
Re mo
val and Installation
Remova

l
1.
Op
en the engine compartment and fit paintwork protection
sheets.
2. Remove the front muffler; refer to Operation 30.10.18 in this
section.

3. Re
move the centre trim panel
from the engine compartment.
1. Remove the left hand side enclosure panel.
2. Remove the centre trim panel.

4. Repo
sition the expansion tank from the mounting.
1. Disconnect the coolant level sensor connector.
2. Remove the nuts which secures the tank.

5. CAUT
ION: Note the position of the upstream and
downstream (where fitted) o xygen sensor multiplugs for
reassembly.
Disconnect the oxygen sensor multiplugs.
Di spl
ace the multiplugs from the engine mounting bracket.

Dis
connect the plug(s) from the oxygen sensor(s)
6.
Re
move the four nuts which se
cure the downpipe catalytic
converter to the exhaust manifold.

2. Fit a ne
w gasket to the mani
fold mating flange on the
downpipe.

3. Fit
the downpipe catalytic converter.
Fit the down
pipe assemb l
y to the manifold.
Fi
t,
but do not fully tighten, the mounting bracket securing

bolts. (Leave loose until the nu ts securing the downpipe to
the exhaust manifold are fitted.)
4. Lower the ramp.

5. Tighte
n the nuts securing the downpipe flange to the manifold
flange.

6. Connec t
the oxygen sensor multiplugs.
Con
n
ect the plug(s) to the respective (previously noted)
sensor(s).
Cor r
ectly position the multiplu
gs on the mounting bracket.
7. Fit the coolant header tank.
1. Reposition the tank and fit the securing nuts.

Exha
ust System - Catalytic Conv
erter LH4.0L SC V8 - AJ26
Remo
val and Installation
Remov
a
l
1.
Op
en the engine compartment and fit paintwork protection
sheets.

2. Re
move the centre trim panel
from the engine compartment.
1. Remove the left hand side enclosure panel.
2. Remove the centre trim panel.

3. Repo
sition the expansion tank from the mounting.
1. Disconnect the coolant level sensor connector.
2. Remove the nuts which secures the tank.

4. CAUT
ION: Note the position of the upstream and
downstream (where fitted) o xygen sensor multiplugs for
reassembly.
Disconnect the oxygen sensor multiplugs.
Di spl
ace the multiplugs from the engine mounting bracket.

Dis
connect the plug(s) from the oxygen sensor(s)

5.
Re
move the four nuts which se
cure the downpipe catalytic
converter to the exhaust manifold.

In
stallation

12
. R
emove gasket from the manifold flange.
Clean and inspect th
e manif
old joint faces.
Clean and inspect th
e threads on th
e downpipe studs.

1. Fit
the oxygen sensor(s).
The downstream sensor i
s
fitt
ed only for North American
markets.
2. Fit a new gasket to the mani fold mating flange on the
downpipe.

3. Fit
the downpipe catalytic converter.
1. Fit the downpipe assembly to the manifold.
Fit,
but do not fully tighten, the mounting bracket securing

bolts. (Leave loose until the nu ts securing the downpipe to
the exhaust manifold are fitted.)
4. Lower the ramp.
5. Tighten the nuts securing the downpipe flange to the manifold
flange.

E
xhaust System - Catalyti
c Converter RH4.0L NA V8 - AJ27/3.2L NA V8 -
AJ26
Re
moval and Installation
Remov

al
1.
O
pen the engine compartment and fit paintwork protection
sheets.
2. Remove the front muffler; refer to Operation 30.10.18 in this
section.

3. CAU
TION: Note the position of the upstream and
downstream (where fitted) o xygen sensor multiplugs for
reassembly.
Disconnect the oxygen sensor multiplugs.
Di
splace the multiplugs from the engine mounting bracket.

D
isconnect the plug(s) from the oxygen sensor(s)

4.
R
emove the four nuts which se
cure the downpipe catalytic
converter to the exhaust manifold.
5. Raise the vehicle on a ramp.

6. R
emove the downpipe catalytic converter.
R

emove the bolts which se
cure the downpipe lower
mounting bracket.
Remove the
downpipe assembly.
7. Remove the oxygen sensor(s).
The downstream sensor i
s fitt
ed only for North American
markets.

In
stallation

8.
Re
move gasket from the manifold flange.
Clean and inspect th
e manif
old joint faces.
Clean and inspect th
e threads on th
e downpipe studs.

1. Fit
the oxygen sensor(s).
The downstream sensor i
s
fitt
ed only for North American
markets.
2. Fit a new gasket to the mani fold mating flange on the
downpipe.

3. Fit
the downpipe catalytic converter.
Fit the down
pipe assemb l
y to the manifold.
Fi
t,
but do not fully tighten, the mounting bracket securing

bolts. (Leave loose until the nu ts securing the downpipe to
the exhaust manifold are fitted.)
4. Lower the ramp.
5. Tighten the nuts securing the downpipe flange to the manifold
flange.