1995 LAND ROVER DISCOVERY fuel

MANIFOLD AND EXHAUST SYSTEM
1
DESCRIPTION AND OPERATION CATALYTIC CONVERTERS - V8i
Description
Catalytic converters which form part of the engine
emission control system, are designed to 'clean' the
exhaust gases, by closely controlling the fuel air ratio
delivered to the engine and converting the residual
exhaust compounds into products more acceptable to
the environment.
The front section of the exhaust system to each
cylinder bank contain the ceramic elements of the
catalytic converters. The oxygen sensors which
transmit information to the fuel ECU for control of the
mixture, are located in the exhaust down pipes.
The Hydrocarbons (HC), Nitogen oxides (NO
x) and
Carbon monoxide (CO) emitted by the engine react
with the catalytic element and exhaust temperature to
convert the toxic gas, into Nitrogen (N), Carbon
dioxide (CO
2) and water vapour.Should the engine be supplied with a rich mixture
causing high CO in the exhaust gas, the ceramic
element will become coated and the useful life of the
catalyst reduced. If the mixture is too weak, excess
oxygen in the exhaust gas will cause the catalysts to
burn out.
1. Catalysts
2. Lambda oxygen sensors

MANIFOLD AND EXHAUST SYSTEM
5
REPAIR INLET MANIFOLD GASKET - Mpi
Service repair no - 30.15.08
Remove
1.Disconnect battery negative lead.
2.Position absorbent cloth around fuel pipe to fuel
rail union. Unscrew union to relieve fuel
pressure. Re-tighten union.
CAUTION: Plug connections.
3.Release clip and remove air cleaner to throttle
housing hose.
4.Disconnect stepper motor multiplug.
5.Disconnect throttle potentiometer multiplug.
6.Release throttle cable from abutment bracket.
7.Release throttle cable from cam. Remove
coolant bypass hose.
8.Disconnect fuel temperature sensor multiplug.
9.Release clip and disconnect brake servo hose
from manifold.

30MANIFOLD AND EXHAUST SYSTEM
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REPAIR 10.Release clip and disconnect breather hose from
manifold.
11.Release 2 bolts securing cam cover brackets to
manifold.
12.Remove 3 bolts securing engine harness to
manifold.
13.Disconnect 3 vacuum hoses from manifold.
14.Release clip and disconnect fuel hose from
pressure regulator.
CAUTION: Plug the connections.
15.Disconnect intake air temperature sensor
multiplug.
16.Disconnect fuel injector harness multiplug.
17.Remove 2 nuts and 7 bolts securing manifold to
cylinder head
18.Remove manifold assembly and collect gaskets.

MANIFOLD AND EXHAUST SYSTEM
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REPAIR Refit
19.Ensure mating faces of inlet manifold and
cylinder head are clean.
20.Fit a new gasket, position inlet manifold to
cylinder head.
21.Fit nuts and bolts, tighten in the order shown to
the correct torque
25Nm
22.Position engine breather hose to manifold and
secure with bolts.
23.Connect fuel injector harness and intake air
temperature sensor multiplug.
24.Connect fuel hose to pressure regulator and
secure with clip.
25.Fit fuel pipe to fuel rail, tighten union to
10Nm
26.Connect vacuum hoses to manifold.
27.Position engine harness and cam cover brackets
to manifold, secure with bolts.
28.Connect breather hose and brake servo hose to
manifold, secure with clips.
29.Connect multiplug to fuel temperature sensor.
30.Connect breather hose to throttle housing and
secure with clip.
31.Connect throttle cable to cam and secure to
abutment bracket.
32.Connect coolant bypass hose to throttle housing.
33.Connect stepper motor and throttle
potentiometer multiplugs.
34.Connect air cleaner hose to throttle housing and
secure with clip.
35.Connect battery negative lead.
36.Adjust throttle cable.EXHAUST MANIFOLD GASKET - Mpi
Service repair no - 30.15.12
Remove
1.Raise vehicle.
2.Loosen 2 nuts securing downpipe to silencer
box.
3.Remove 4 nuts securing downpipe to exhaust
manifold.
4.Release downpipe from exhaust manifold.
5.Discard gasket.

MANIFOLD AND EXHAUST SYSTEM
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REPAIR MANIFOLD CHAMBER GASKET - Mpi
Service repair no - 30.15.37
Remove
1.Disconnect battery negative lead.
2.Position absorbent cloth around fuel pipe to fuel
rail union. Loosen union to relieve pressure.
Re-tighten union.
3.Release clip and remove air cleaner to throttle
housing hose.
4.Disconnect stepper motor and throttle
potentiometer multiplugs.
5.Release clip and disconnect breather hose from
throttle housing.
6.Release throttle cable from abutment bracket.
7.Release throttle cable from cam. Remove
coolant bypass hose from throttle housing.
8.Disconnect fuel temperature sensor multiplug.
9.Release clip and disconnect brake servo hose
from manifold.

30MANIFOLD AND EXHAUST SYSTEM
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REPAIR 10.Release clip and disconnect breather hose from
manifold.
11.Release 2 bolts securing camshaft cover
brackets to manifold.
12.Disconnect 4 vacuum hoses from manifold.
13.Remove 6 bolts securing manifold chamber to
lower manifold.
14.Remove manifold chamber and collect gaskets.
Refit
NOTE: For torque values.See
Specifications, torque, Torque Values
15.Ensure mating faces of manifold chamber and
lower manifold are clean.
16.Fit a new gasket, position manifold chamber to
lower manifold.
17.Fit bolts, tighten to the correct torque.
18.Connect vacuum hoses to manifold.
19.Position camshaft cover brackets to manifold,
secure with bolts.
20.Connect breather hose and brake servo hose to
manifold, secure with clips.
21.Connect multiplug to fuel temperature sensor.
22.Connect breather hose to throttle housing and
secure with clip.
23.Connect throttle cable to cam and secure to
abutment bracket.
24.Connect coolant bypass hose to throttle housing.
25.Connect stepper motor and throttle
potentiometer multiplugs.
26.Connect air cleaner hose to throttle housing and
secure with clip.
27.Reconnect battery negative lead.
28.Adjust throttle cable.

MANIFOLD AND EXHAUST SYSTEM
1
SPECIFICATIONS, TORQUE TORQUE VALUES
NOTE: Torque wrenches should be regularly checked for accuracy to ensure that all fixings are
tightened to the correct torque.
Nm
MANIFOLDS AND EXHAUSTS - Mpi
Inlet manifold nuts and bolts 25......................................................................
Fuel pipe to fuel rail 10....................................................................................
Exhaust manifold nuts 45................................................................................
Exhaust frontpipe to manifold 10....................................................................
Exhaust downpipe to silencer box 30.............................................................
Manifold chamber gasket 10...........................................................................

ZF
5
REPAIR Remove
1.Select low range with transfer gear lever.
2.Remove knob and gaiter from transfer gear
lever.
3.Disconnect battery terminals.
4.Remove insulation pad from rocker cover and
inlet manifold.
5.On LH drive vehicles only, disconnect multi-plug
from top of brake fluid reservoir.
6.Release electrical harness from clips along top
of bulkhead and pull over to one side.7.Remove bolt securing transfer and main gearbox
breather pipe clip to rear of cylinder head.
8.Disconnect kick down cable at fuel injection
pump.
9.Drain coolant from cooling system.
10.Disconnect top hose from radiator.
11.Disconnect turbo charger hose from inter-cooler.
12.Remove starter heat shield.