1999 LAND ROVER DISCOVERY Workshop Manual

EMISSION CONTROL - V8
17-2-56 REPAIRS
Sensor - heated oxygen (HO2S) - pre-
catalytic converter
$% 19.22.16
Remove
1.Raise vehicle on a ramp.
2.Release HO
2S multiplug from support bracket.
3.Release HO
2S harness from clip and
disconnect multiplug from HO
2S .
4.Using a 22 mm crow's-foot spanner, remove
HO
2S.
CAUTION: HO
2 sensors are easily damaged
by dropping, excessive heat or
contamination. Care must be taken not to
damage the sensor housing or tip.Refit
1.Clean sensor and exhaust pipe mating
surfaces.
2.If refitting existing sensor, apply anti-seize
compound to sensor threads.
WARNING: Some types of anti-seize
compound used in service are a health
hazard. Avoid skin contact.
NOTE: A new HO
2 sensor is supplied pre-
treated with anti-seize compound.
3.Fit a new sealing washer to HO
2S
4.Fit HO
2S and tighten to 45 Nm (33 lbf.ft).
5. Connect multiplug to HO
2S, and secure to
support bracket and harness clip.
6.Lower vehicle.

EMISSION CONTROL - V8
REPAIRS 17-2-57
Sensor - heated oxygen (HO2S) - post-
catalytic converter
$% 19.22.17
Remove
1.Raise vehicle on ramp.
2.Release HO
2S multiplug from support bracket.
3.Disconnect HO
2S multiplug from harness.
4.Using a 22 mm crowsfoot spanner, remove
HO
2S.
CAUTION: HO2 sensors are easily damaged
by dropping, excessive heat or
contamination. Care must be taken not to
damage the sensor housing or tip.Refit
1.Clean sensor and exhaust pipe mating
surfaces.
2.If refitting existing sensor, apply anti-seize
compound to sensor threads.
WARNING: Some types of anti-seize
compound used in service are a health
hazard. Avoid skin contact.
NOTE: A new HO2 sensor is supplied pre-
treated with anti-seize compound.
3.Fit a new sealing washer to HO
2S
4.Fit HO
2S and tighten to 45 Nm (33 lbf.ft).
5. Connect HO
2S multiplug to harness and fit
harness to bracket.
6.Secure harness to clip.
7.Lower vehicle.

EMISSION CONTROL - V8
17-2-58 REPAIRS
Control Valve - Secondary Air Injection
(SAI)
$% 17.25.02
Remove
1.Release clip and disconnect air hose from
valve.
2.Disconnect vacuum hose from valve.
3.Remove 2 bolts securing valve to air manifold.
4.Remove valve and discard gasket.
Do not allow dirt or debis to enter the air
manifold.
Refit
1.Clean SAI control valve and mating face on
manifold.
2.Fit new gasket and fit valve. Tighten bolts to 10
Nm (7 lbf.ft).
3.Connect vacuum hose.
4.Connect air hose and secure with clip.
Reservoir - Vacuum - Secondary Air
Injection (SAI) - up to 03MY
$% 17.25.04
Remove
1.Disconnect 2 vacuum hoses from reservoir.
2.Remove bolt securing reservoir to mounting
bracket and collect reservoir.
Refit
1.Position reservoir to mounting bracket and
tighten bolt to 10 Nm.
2.Connect vacuum hoses to reservoir.
M17 0222
1
2
3
4
M17 02272
1
1

EMISSION CONTROL - V8
REPAIRS 17-2-59
Reservoir - vacuum - Secondary Air
Injection (SAI) - from 03MY
$% 17.25.04
Remove
1.Disconnect 2 vacuum pipes from air reservoir.
2.Remove bolt securing air reservoir to air pump
and remove the reservoir.
Refit
1.Position air reservoir to air pump, fit bolt and
tighten to 10 Nm (7 lbf.ft).
2.Connect vacuum pipes to the air reservoir.
Pump - Air - Secondary Air Injection
(SAI)
$% 17.25.07
Remove
1.Disconnect multiplug from air pump.
2.Release clip and disconnect air hose from air
pump.
3.Remove bolt securing air pump bracket to
body.
4.Remove air pump and bracket assembly.
5.Remove 3 nuts securing bracket to air pump
and collect bracket.
6.Remove 3 mountings from air pump.
Refit
1.Fit mountings to air pump and tighten to 10
Nm.
2.Fit bracket to air pump mountings and tighten
nuts to 10 Nm.
3.Position air pump assembly and tighten bolt to
20 Nm.
4.Connect air hose to SAI pump.
5.Connect multiplug to air pump.
M17 0225
2
1
3
4
M17 0226
5
5
6

EMISSION CONTROL - V8
17-2-60 REPAIRS
Air Manifold - LH - Secondary Air
Injection (SAI)
$% 17.25.17
Remove
1.Remove SAI control valve.

+ EMISSION CONTROL - V8,
REPAIRS, Control Valve - Secondary Air
Injection (SAI).
2.Disconnect 2 air manifold unions from adapters
in cylinder head.
CAUTION: Take care that air manifold pipes
are not damaged during removal of union
nuts.
3.Remove 2 nuts securing air manifold bracket to
inlet manifold.
4.Remove air manifold.Refit
1.Clean air manifold and cylinder head adapters.
2.Apply a small amount of engine oil to top of air
manifold union nuts and around air manifold
pipes.
3.Position air manifold and finger tighten both
union nuts.
CAUTION: Finger tighten union nuts as far
as possible, damage to air manifold pipes or
adapters may result if this is not done.
4.Tighten air manifold unions to 25 Nm (18 lbf.ft).
CAUTION: Ensure that air manifold pipes
are not distorted during tightening
operation.
5.Fit nuts securing air manifold to inlet manifold
and tighten to 25 Nm (18 lbf.ft).
6.Fit SAI control valve.

+ EMISSION CONTROL - V8,
REPAIRS, Control Valve - Secondary Air
Injection (SAI).
M17 0234
4
3
2
2

EMISSION CONTROL - V8
REPAIRS 17-2-61
Air Manifold - RH - Secondary Air
Injection (SAI)
$% 17.25.18
Remove
1.Remove SAI control valve.

+ EMISSION CONTROL - V8,
REPAIRS, Control Valve - Secondary Air
Injection (SAI).
2.Remove heater feed pipe.

+ HEATING AND VENTILATION,
REPAIRS, Pipe - Heater - Feed.
3.Disconnect 2 air manifold unions from adapters
in cylinder head.
CAUTION: Take care that air manifold pipes
are not damaged during removal of union
nuts.
4.Remove nut securing air manifold bracket to
inlet manifold.
5.Remove air manifold.Refit
1.Clean air manifold and cylinder head adaptors.
2.Apply a small amount of engine oil to top of air
manifold union nuts and around air manifold
pipes.
3.Position air manifold and finger tighten both
union nuts.
CAUTION: Finger tighten union nuts as far
as possible, damage to air manifold pipes or
adapters may result if this is not done.
4.Tighten air manifold unions to 25 Nm (18 lbf.ft).
CAUTION: Ensure that air manifold pipes
are not distorted during tightening
operation.
5.Fit nut securing air manifold to inlet manifold
and tighten to 25 Nm (18 lbf.ft).
6.Fit heater feed pipe.

+ HEATING AND VENTILATION,
REPAIRS, Pipe - Heater - Feed.
7.Fit SAI control valve.

+ EMISSION CONTROL - V8,
REPAIRS, Control Valve - Secondary Air
Injection (SAI).
M17 0223
43
3
5

EMISSION CONTROL - V8
17-2-62 REPAIRS
Solenoid - Vacuum - Secondary Air
Injection (SAI)
$% 17.25.47
Remove
1.Release multiplug from solenoid.
2.Disconnect 2 vacuum hoses from solenoid.
3.Release solenoid from mounting bracket and
remove.
Refit
1.Secure solenoid to mounting bracket.
2.Connect vacuum hoses and multiplug to
solenoid.
Pipe - Secondary Air Injection (SAI)
$% 17.25.59
Remove
1.Loosen clip securing RH SAI control valve hose
to air injection pipe.
2.Release hose from air injection pipe.
3.Loosen clip securing SAI pump hose to air
injection pipe.
4.Release hose from air injection pipe.
5.Loosen clip securing LH SAI control valve hose
to air injection pipe.
6.Release hose from air injection pipe.
7.Disconnect multiplug from SAI vacuum
solenoid.
M17 0236
1
2
2
3
M17 0230

EMISSION CONTROL - V8
REPAIRS 17-2-63
8.Remove 2 nuts securing air injection pipe to air
intake plenum.
9.Release pipe from clip on rear of air intake
plenum.
10.Release 3 clips securing harness to engine bay
bulkhead.
11.Position container to collect any coolant
spillage.
12.Release clips securing heater hoses to heater.
13.Release hoses from heater.
14.With assistance, manoeuvre air injection pipe
from engine bay.Refit
1.With assistance, manoeuvre air injection pipe
into engine bay and secure onto clip at rear of
air intake plenum.
2.Connect heater hoses to heater and secure
with clips.
3.Reposition harness along engine bay bulkhead
and secure with clips.
4.Fit and tighten nuts securing air injection pipe to
air intake plenum.
5.Connect multiplug to SAI vacuum solenoid.
6.Connect air pump hose to air injection pipe and
secure with clip.
7.Connect LH and RH SAI control valve hoses to
air injection pipe and secure with clips.
8.Remove container.
9.Top up engine coolant.

+ MAINTENANCE, PROCEDURES,
Cooling system.
M17 0231
M17 0232
M17 0233