Emission Cont rol – V6 S/C Engine Page 6E2–1

Page 6E2–1

Section 6E2

Emission Control – V6 S/C 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

Emission Cont rol – V6 S/C Engine Page 6E2–2

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1 General Information

MY 2004 WK Series Emission Control – V6 S/C Engine information carries over from MY 2003 VY Series vehicles. For

all emission control information, refer to Section 6E2 Emission Control – V6 S/C Engine in the MY 2003 VY and V2

Series Service Information.

1.1 Euro 2 Emission Standards

Euro 2 is a European standard setting vehicle emissions 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 – V6 S/C Engine Page 6E2–3

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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 V6 supercharged exhaust system is similar to VY vehicles fitted with V6 supercharged engines, except that new

heated oxygen sensors are used and the catalytic converter catalyst specifications have been revised to improve catalyst

performance. For further information on V6 supercharged exhaust systems, refer to Section 8B Exhaust System in the

MY 2003 VY and V2 Series Service Information.

Emission Cont rol – V6 S/C Engine Page 6E2–4

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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.