Front Pipe; Intermediate Pipe; Unscrew Turbocharger Oil Supply Pipe Banjo Union; Exhaust Manifold Retaining Nuts - Opel Zafira B MPV 2006 Owners Workshop Manual

48•16 Fuel and exhaust systems - diesel engines
19.31 Unscrew the turbocharger oil supply
pipe banjo union (arrowed) and collect the
two copper washers
31 Unscrew the turbocharger oil supply pipe
banjo union from the cylinder block and collect
the two copper washers (see illustration).
32 Disconnect the vacuum hose from the
turbocharger wastegate actuator.
33 On models equipped with air conditioning,
undo the three bolts securing the compressor
to the mounting bracket. Move the compressor
to one side and suitably support it without
straining the refrigerant pipes.
34 Unscrew the eight nuts securing the
exhaust manifold to the cylinder head (see
illustration). Note that new nuts will be
required for refitting. Withdraw the manifold
and turbocharger assembly from the mounting
studs, manipulate it sideways, and remove
from under the car. Recover the gasket.
20.5 Undo the three nuts securing the
front pipe flange to the intermediate pipe
flange
20.6b ... and the two bolts (arrowed)
securing the support clamp to the
transmission bracket
19.34 Exhaust manifold retaining nuts
(arrowed)
Refitting
35 Refitting is the reverse of removal, noting
the following points.
a) Ensure all mating surfaces are clean and
dry and renew all gaskets, seals and
copper washers.
b) Fit the new manifold nuts and tighten
them evenly and progressively to the
specified torque, working in
a
diagonal
sequence.
c) Tighten all other retaining nuts and bolts
to the specified torque (where given).
d) Refit the exhaust system front pipe as
described in Section
20.
e) On automatic transmission models, refit
the front bumper
as described in Chap-
ter
11.
20.6a Undo the three nuts (two arrowed)
securing the front pipe to the catalytic
converter •••
20.10 Unscrew the retaining nut (arrowed)
and remove the temperature sensor from
the diesel particulate filter
f) On completion refill the cooling system as
described in Chapter 1 B and, if
necessary,
top-up the oil level as described in
'Weekly checks'.
g) On starting the engine for the first time,
allow the engine to idle for
a
few minutes
before increasing the engine speed; this
will allow oil to be circulated around the
turbocharger bearings.
General information
1 The exhaust system consists of three main
sections comprising a front pipe, an intermediate
pipe incorporating the diesel particulate filter
and a tailpipe incorporating the rear silencer. A
primary catalytic converter is fitted between the
exhaust manifold and front pipe.
2 The front pipe is attached to the catalytic
converter by a flange joint secured by nuts.
The intermediate pipe is attached to the front
pipe by a flange joint secured by nuts, and the
tailpipe is attached to the intermediate pipe by
an overlap joint secured by a clamp.
3 The front pipe is fitted with a flexible section
to allow for exhaust system movement and
the system is suspended throughout its entire
length by rubber mountings.
Removal
4 To remove the various parts of the system, first
jack up the front or rear of the car, and support
it on axle stands. Alternatively, position the car
over an inspection pit, or on car ramps. Where
necessary, undo the retaining screws, release
the clips and remove the engine undertray.
Front pipe
5 Undo the three nuts securing the front pipe
flange to the intermediate pipe flange (see
illustration).
6 Undo the three nuts securing the front pipe
to the catalytic converter, and the two bolts
securing the support clamp to the transmission
bracket (see illustrations). Free the front pipe
from the converter and recover the gasket.
While doing this, take care to support the
flexible section. Note: Angular movement in
excess of 10° can cause permanent damage
to the flexible section.
7 Slide the front pipe off the intermediate pipe
studs and remove the front pipe from under
the car.·
Intermediate pipe
8 Remove the tailpipe as described later in
this Section.
9 Release the retaining clips and disconnect
the two differential pressure sensor vacuum
hoses from the two pipes just forward of the
diesel particulate filter.
10 Unscrew the retaining nut and remove the
temperature sensor from the diesel particulate
filter (see illustration).