Emission Cont rol – GEN III V8 Engine Page 6E3–1

Page 6E3–1

Section 6E3

Emission Control – GEN III V8 Engine

ATTENTION

Before performing any Service Operation or other procedure described in this Section, refer to Section 00

Warnings, Cautions and Notes for correct workshop practices with regard to safety and/or property damage.

1 General Information............................................................................................................................... 2

1.1 Euro 2 Emission Standards...................................................................................................................................2

1.2 Changes to Vehicle................................................................................................................................................3

1.3 Emission Control....................................................................................................................................................4

2 Service Operations................................................................................................................................ 5

2.1 References..............................................................................................................................................................5

Heated Oxygen Sensors (HO2S)............................................................................................................................5

Emission Cont rol – GEN III V8 Engine Page 6E3–2

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1 General Information

With the following exceptions, MY 2004 WK Series Emission Control – GEN III V8 Engine information carries over from

MY 2003 VY Series vehicles. For information not contained within this Section, refer to Section 6E3 Emission Control –

Gen III V8 Engine in the MY 2003 VY and V2 Series Service Information.

The vehicle has been configured to comply with the Euro 2 vehicle emission standards.

1.1 Euro 2 Emission Standards

Euro 2 is a European standard setting vehicle emission targets to encourage vehicle manufacturers to reduce harmful

vehicle emissions such as carbon monoxide (CO), hydrocarbons (HC) and the various oxides of nitrogen (NOx).

Australian Design Rule 79/00 implements the 'Euro 2' exhaust and evaporative emissions requirements for light vehicles

to reduce air pollution. The following tests are prescribed:

• average tailpipe emissions after a cold start,

• carbon monoxide emission at idling speed,

• emission of crankcase gases,

• evaporative em is sion s, and

• durability of pollution-control devices.

Emission Cont rol – GEN III V8 Engine Page 6E3–3

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1.2 Changes to Vehicle

MY2004 WK vehicles have been configured to comply with Euro 2 vehicle emission standards by refinements in engine

calibration and optimisati on of the ex haust sy ste m cata ly tic c onverter configuratio ns.

As optimum catalytic converter performance is reached above 500°C, a close coupling of the catalytic converter with the

exhaust manifo ld ensures that, upon engine startup, the engine ex haust gas es can heat the cataly tic conv erter to an

optimum operating temperature in as short a time as possible.

The major modifications made to the V8 exhaust system from previous Series vehicles include revised front exhaust

assemblies incorporating close-coupled catalytic converters and new on-pipe heat shields. The oxygen sensors are

moved towards the engine and are positioned between the exhaust manifold and the catalytic converter. Performance

exhaust is availa ble as an option.

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1.3 Emission Control

The Powertrain Control Module (PCM) controls the air-fuel mixture delivered to the engine. Oxygen sensors are used to

provide feedback to the PCM to ensure that an ideal air-fuel ratio is maintained.

Exhaust emissions contain a variety of gases that include water vapour (H2O ), carbon diox ide (CO2), carbon monoxide

(CO), hydrocarbons (HC) and various oxides of nitrogen (NOx). Three-way catalytic converters incorporated along the

front exhaust pipe assemblies convert the gaseous pollutants carbon monoxide (CO), hydrocarbons (HC) and the

various ox ides of nitrogen (NO x) to less toxic gases that include water (H2O), carbon dioxide (CO2) and nitrogen (N2).

The exhaust system fitted to a particular vehicle depends on the engine type and model specifications.

For further information on the revised exhaust system, refer to Section 8B Exhaust System.

Emission Cont rol – GEN III V8 Engine Page 6E3–5

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2 Service Operations

2.1 References

Section 6E3 Emission Control – Gen III V8 Engine in the MY 2003 VY and V2 Series Service Information, contains

reference to other MY 2003 VY and V2 Series Sections. Due to different components and maintenance procedures, the

following references must be substituted for the corresponding reference in Section 6E3 Emission Control – Gen III V8

Engine in the MY 2003 VY and V2 Series Service Information.

Heated Oxygen Sensors (HO2S)

For service procedures of the heated oxygen sensors, refer to Section 6C3, 6 Service Operations.