Page 597 of 652

19B-15
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 772 – D7F
19B
REMOVAL
I - REMOVAL PREPARATION OPERATION
aPosition the vehicle on a two-post lift (see Vehicle:
Towing and lifting) (02A, Lifting equipment).
aDisconnect the downstream oxygen sensor connec-
tor.
aUnclip the wiring harness from the downstream oxy-
gen sensor.
aDisconnect the upstream oxygen sensor connector.
aUnpick the wiring harness from the upstream oxy-
gen sensor.
II - OPERATION FOR REMOVAL OF PART
CONCERNED
aRemove:
-the clip (1) between the catalytic converter and the
intermediate pipe,
-the bolts (2) from the exhaust flange,
-the catalytic converter,
-the exhaust pipe sealing ring on the catalytic con-
verter.
Dismantling the catalytic converter
aUsing the (Mot. 1495-01), remove:
-the downstream oxygen sensor,
-the upstream oxygen sensor.
REFITTING
I - REFITTING PREPARATION OPERATION
Reassembling the catalytic converter
aUsing the (Mot. 1495-01), refit:
-the upstream oxygen sensor,
-the downstream oxygen sensor.
II - REFITTING OPERATION FOR PART
CONCERNED
a
aRefit:
-the catalytic converter,
-the exhaust bracket bolts,
-the clip between the catalytic converter and the in-
termediate pipe.
aTighten:
-the exhaust bracket bolts,
-the clip between the catalytic converter and the in-
termediate pipe.
III - FINAL OPERATION
aClip the upstream oxygen sensor wiring harness into
place.
aConnect the upstream oxygen sensor connector.
aAttach the downstream oxygen sensor wiring har-
ness.
aConnect the downstream oxygen sensor connector. Special tooling required
Mot. 1495-0122 mm socket for removal -
refitting of oxygen sensors.
121731
WARNING
Always replace the sealing ring between the cat-
alytic con verter and the exhaust pipe with a new
component.
Page 598 of 652

19B-16
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
REMOVAL
I - REMOVAL PREPARATION OPERATION
aPosition the vehicle on a two-post lift (see Vehicle:
Towing and lifting) (MR 411, 02A, Lifting equip-
ment).
aDisconnect the battery (see Battery: Removal - Re-
fitting) (MR 411, 80A, Battery).
aRemove:
-the air filter unit (see 12A, Fuel mixture, Air filter
unit: Removal - Refitting, page 12A-13) ,
-the air filter box strut bolt,-the air filter box strut,
-the upstream oxygen sensor (see 17B, Petrol in-
jection, Oxygen sensors: Removal - Refitting,
page 17B-13) . Tightening torquesm
catalytic converter lower
bracket bolt on the gear-
box44 N.m
bolts of the catalytic
converter lower bracket
on the engine25 N.m
side bracket bolts on the
catalytic converter21 N.m
side bracket bolts on the
engine21 N.m
catalytic converter nuts
on the turbocharger (ini-
tial torque)20 N.m
catalytic converter nuts
on the turbocharger30 N.m
bolts of the catalytic
converter lower bracket
on the catalytic con-
verter (initial torque)20 N.m
bolts of the catalytic
converter lower bracket
on the catalytic con-
verter30 N.m
exhaust downpipe bolts21 N.m
catalytic converter strut
nut21 N.m
catalytic converter strut
bolt on the rocker cover21 N.m
Page 599 of 652
19B-17
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
aRemove the turbocharger air outlet rigid pipe bolt (1)
from the throttle valve.
aDetach the turbocharger air outlet pipe from the tur-
bocharger in the direction of the arrow (2) .
aDisconnect the turbocharger air outlet pipe from the
turbocharger.aMove aside the turbocharger air outlet pipe.
aRemove:
-the catalytic converter strut nut (4) ,
-the catalytic converter strut bolt (5) from the rocker
cover,
-the turbocharger strut.
-the rear suspended engine mounting (see 19D,
Engine mounting, Lower engine tie-bar: Re-
moval - Refitting, page 19D-18) .
122834
122673
Note:
Removing the heat-resistance protector clip (3)
requires the turbocharger air outlet pipe to be
replaced.
120959
Page 600 of 652
19B-18
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
aRemove the exhaust bracket bolts (6) at the catalytic
converter outlet.
aUndo the intermediate pipe clip.
aRemove the intermediate pipe clip.
aRemove the exhaust downpipe.aRemove:
-the side bracket bolts (7) from the engine,
-the side bracket bolts (8) from the catalytic convert-
er,
-the side exhaust bracket from the catalytic convert-
er.
aLoosen the bolts (9) of the catalytic converter lower
bracket on the catalytic converter.
aRemove:
-the bolts (10) of the catalytic converter lower brack-
et on the engine,
-the bolt (11) securing the catalytic converter lower
bracket on the gearbox,
-the catalytic converter lower exhaust bracket.
108817120960
Page 601 of 652

19B-19
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
II - OPERATION FOR REMOVAL OF PART
CONCERNED
aDisconnect the catalytic converter downstream oxy-
gen sensor connector (12) .
aUnclip the downstream oxygen sensor connector
from the catalytic converter.
aUnpick the catalytic converter downstream oxygen
sensor wiring harness (13) .aRemove:
-the catalytic converter nuts (14) on the turbocharg-
er,
-the catalytic converter by rotating it while tilting the
engine,
-the catalytic converter seal on the turbocharger.
REFITTING
I - REFITTING PREPARATION OPERATION
aAlways replace:
-the catalytic converter seal,
-the catalytic converter nuts on the turbocharger.
II - REFITTING OPERATION FOR PART
CONCERNED
aRefit:
-the catalytic converter seal on the turbocharger,
-the catalytic converter by rotating it while tilting the
engine,
121130
122671
IMPORTANT
Catalytic converters contain cer amic fibres, these
are contained within a closed unit, and cannot
disperse. Drilling or cutting catalytic converters is
prohibited.
Page 602 of 652

19B-20
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
-the new nuts with the catalytic converter spacers
on the turbocharger.
aAttach the downstream oxygen sensor wiring har-
ness to the catalytic converter.
aClip on the catalytic converter downstream oxygen
sensor connector.
aConnect the catalytic converter downstream oxygen
sensor connector.
III - FINAL OPERATION
aRefit:
-the catalytic converter lower exhaust bracket,
-the bracket bolt on the gearbox,
-the bracket bolts on the engine,
-the catalytic converter side exhaust bracket,
-the catalytic converter side bracket bolts,
-the engine side bracket bolts.
aTorque tighten:
-the catalytic converter lower bracket bolt on the
gearbox (44 N.m),
-the bolts of the catalytic converter lower brack-
et on the engine (25 N.m),
-the side bracket bolts on the catalytic converter
(21 N.m),
-the side bracket bolts on the engine (21 N.m),
-the catalytic converter nuts on the turbocharger
(initial torque) (20 N.m),
-the catalytic converter nuts on the turbocharger
(30 N.m),
-the bolts of the catalytic converter lower brack-
et on the catalytic converter (initial torque) (20
N.m),
-the bolts of the catalytic converter lower brack-
et on the catalytic converter (30 N.m).
aRefit:
-the exhaust downpipe,
-the intermediate pipe clip.
aTighten the intermediate pipe clip.
aRefit the exhaust downpipe bolts on the catalytic
converter.
aTorque tighten the exhaust downpipe bolts (21
N.m).aRefit:
-the rear suspended engine mounting (see 19D,
Engine mounting, Lower engine tie-bar: Re-
moval - Refitting, page 19D-18) ,
-the turbocharger strut.
-the catalytic converter strut bolt on the rocker cov-
er,
-the catalytic converter strut nut.
aTorque tighten:
-the catalytic converter strut nut (21 N.m),
-the catalytic converter strut bolt on the rocker
cover (21 N.m).
aPosition the turbocharger air outlet pipe.
aPush the turbocharger air outlet pipe clip (15) in the
direction of the arrow.
aConnect the turbocharger air outlet pipe onto the tur-
bocharger.
aRefit:
-the turbocharger air outlet rigid pipe bolt on the
throttle valve,
-the upstream oxygen sensor (see 17B, Petrol in-
jection, Oxygen sensors: Removal - Refitting,
page 17B-13) ,
-the air filter box strut,
-the air filter box strut bolt,
-the air filter unit (see 12A, Fuel mixture, Air filter
unit: Removal - Refitting, page 12A-13) .
122666
Page 603 of 652
19B-21
EXHAUST
Catalytic converter: Removal - Refitting
D4F, and 780 or 782
19B
aConnect the battery (see Battery: Removal - Refit-
ting) (MR 411, 80A, Battery).
Page 604 of 652
19B-22
EXHAUST
Catalytic converter: Removal - Refitting
K4M
19B
aThe catalytic converter cannot be separated from
the exhaust manifold.
Replace the "exhaust manifold - catalytic converter"
assembly if the catalytic converter is faulty (see 12A,
Fuel mixture, Exhaust manifold: Removal - Refit-
ting, page 12A-48) .