manifold JAGUAR X308 1998 2.G Manual Online

3. Conne
ct CMP sensor connector.

4. Connect
fuel feed pipe to inlet manifold.
R

emove blanking plugs.
Install and lubricate new O-r

ing.

5. Install
bolts securing fuel feed
pipe to the inlet manifold.
6. Install coolant expansion tank.

Exhaust System -
Torques


ComponentNm
Nut - Downpipe catalytic converter to exhaust manifold14 - 18
Bolt - Downpipe catalytic converter to lower mounting bracket39 - 51
Bolt - Front muffler mounting to gearbox (SC)22 - 28
Bolt - Front muffler mounting to front muffler cross brace (SC)22 - 28
Bolt - Over-axle mounting to rear suspension A-frame22 - 28
Torca clamps52 - 68
Oxygen sensor to downpipe40 - 50

The left-hand and right-hand do wnpipe assemblies feature:
Catalytic converter with palladium / rhodium coated elem ents. The elements are uncoated for markets with only
leaded fuel.
Retained to the exhaust manifold flange by four thread ed studs. Joint-to-joint sealing is with a gasket. Engine-mounted bracket providing downpipe mounting by two nuts to the torque converter housing and two bolts to
the downpipe.
Front Muffler Assembly
ItemPart NumberDescription
1—Downpipe catalytic converter
2—Upstream heated oxygen sensor
3—Downstream oxygen sensor (North American markets only)
4—Engine mounting bracket (LHS and RHS)

Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to B2
B2: CHECK FOR LOW EX HAUST 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 B3
No Rectify possible leaking exhaust manifold / catalyst, general
causes of an over rich mixture and engine cooling system
operation. Test the system for correct operation.
GO to B8
B3: CHECK FOR O2 SENS OR HEATER CONTINUITY
Ignition switch to position 0 1
Disconnect EM021
Bracket on top of gearbox or Bulkhead rear of engine
2
With EM021 disconnected, measure the resistance between
EM021/001 and EM021/002. 3
Is the resistance between 4 and 10 OHM?
Yes
GO to B4
No Renew O2 sensor, reconnect plug(s).
GO to B8
B4: CHECK FOR O2 SENSOR FAILURE

Connect the scan tool 1
Have the DTC(s) and freeze frame data been recorded?
Yes GO to D2
D2: CHECK FOR LOW EXHAUST TEMPERATURE
Check the engine and exhaust system for correct operation
and normal running temperature 1
Is the engine and exhaust system operating correctly and up to
normal running temperature?
Yes GO to D3
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 D7
D3: CHECK FOR O2 SENSOR FAILURE
Run the engine for a period to warm the sensor and then
maintain a steady speed of approximately 2500 rpm. 1
Measure the voltage between EM022/001 and EM022/002. 2

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.

I
nstallation

7.
R
aise the vehicle on a ramp.

8. R
emove the downpipe catalytic converter.
R

emove the bolts which se
cure the downpipe lower
mounting bracket.
Remove the
downpipe assembly.

9. R
emove the oxygen sensor(s).
The downstream sensor i

s fitt
ed only for North American
markets.
10. Remove gasket from the manifold flange.
Clean and inspect th
e manifold joint faces.
Clean and inspect th

e threads
on the downpipe studs.
1. Fit the oxygen sensor(s).
The downstream sensor i
s fitt
ed only for North American
markets.

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.