24183 version 1
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Demonstrate knowledge of engine tuning procedures and equipment
malfunction causes on CNG fuelled vehicles
Level
4
Credits
2
Purpose
This theory-based unit standard is for people in automotive and related
industries. People credited with this unit standard are able to demonstrate
knowledge of engine tuning procedures and equipment malfunction causes
on compressed natural gas (CNG) fuelled vehicles.
Subfield
Motor Industry
Domain
Automotive Fuel Systems and Exhaust
Status
Registered
Status date
25 January 2008
Date version published
25 January 2008
Planned review date
31 December 2012
Entry information
Open.
Replacement information
This unit standard and unit standard 24184 replaced unit
standard 952.
Accreditation
Evaluation of documentation and visit by NZQA and
industry.
Standard setting body (SSB)
NZ Motor Industry Training Organisation (Incorporated)
Accreditation and Moderation Action Plan (AMAP) reference
0014
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
1
Legislation and publications relevant to this unit standard include but are not limited
to – Health and Safety in Employment Act 1992; Traffic Regulations 1976; Land
Transport Rules: Vehicle Repair 1998, Rule 34001; Vehicle Standards Compliance
2002, Rule 35001/1; Vehicle Standards Compliance Amendment 2005, Rule
35001/2; New Zealand Standard AS/NZS 2739:2003 Natural gas (CNG) fuel systems
for vehicle engines.
 New Zealand Qualifications Authority 2016
24183 version 1
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2
Land Transport Rules are produced for the Minister of Transport by Land Transport
New Zealand. These rules are available online at
http://www.landtransport.govt.nz/rules/.
New Zealand Standards are available from Standards New Zealand, Private Bag
2439, Wellington; phone 04 498 5990; or website http://www.standards.co.nz.
3
Definitions
CNG equipment manufacturer instructions refer to specifications and instructions
provided by the equipment manufacturer for the correct installation and operation of
the CNG component(s) or system(s) provided by that manufacturer.
Company requirements refer to instructions to staff on policy and procedures which
are documented in memo or manual format and are available in the workplace.
These requirements include but are not limited to – company specifications and
procedures, work instructions, manufacturer specifications, product quality
specifications, and legislative requirements.
Elements and performance criteria
Element 1
Demonstrate knowledge of engine tuning procedures and equipment malfunction causes
on CNG fuelled vehicles.
Performance criteria
1.1
Problems that may affect engine operation following the fitment of conversion
systems are described in accordance with CNG equipment manufacturer
instructions.
Range
1.2
Problems that may occur with CNG components in service are described in
accordance with CNG equipment manufacturer instructions.
Range
1.3
mechanical and electrical faults, lack of servicing, external
problems affecting performance.
The procedure to perform on-road acceleration tests is described in accordance
with company requirements.
Range
1.4
malfunctions related to fuel supply and gas usage.
hesitation, misfiring, flat spots, overall performance.
The use of a rolling chassis dynamometer and an infra-red exhaust gas
analyser for carrying out adjustment and test procedures on an engine
operating on dual fuel is explained in accordance with CNG manufacturer
equipment instructions.
Range
engine under loading conditions throughout revolutions per minute
(RPM) range.
 New Zealand Qualifications Authority 2016
24183 version 1
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1.5
The modification requirements for vehicles to run on dedicated CNG are
explained in accordance with CNG manufacturer equipment instructions.
Range
1.6
Legislative requirements when carrying out repairs and maintenance to vehicles
equipped with CNG fuel systems are described.
Range
1.7
includes but is not limited to – removal of existing fuel system
components, fitting of gas components, alterations to compression
ratio, ignition components, ignition timing, exhaust emission
controls, air intake systems, valve and valve seat modifications,
turbocharging, intercooling.
AS/NZS 2739, Traffic Regulations, Land Transport Rules (Vehicle
Repair, Vehicle Standards Compliance).
Procedures to maintain a CNG fuel system are described in accordance with
service information and legislative requirements.
Range
filter cleaning, regulator draining, air filter, leak detection, security
of components, hose condition, mixer attachment.
Please note
Providers must be accredited by NZQA, or an inter-institutional body with delegated
authority for quality assurance, before they can report credits from assessment against
unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be accredited by NZQA before they can register
credits from assessment against unit standards.
Accredited providers and Industry Training Organisations assessing against unit standards
must engage with the moderation system that applies to those standards.
Accreditation requirements and an outline of the moderation system that applies to this
standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The
AMAP also includes useful information about special requirements for organisations
wishing to develop education and training programmes, such as minimum qualifications for
tutors and assessors, and special resource requirements.
Comments on this unit standard
Please contact the NZ Motor Industry Training Organisation (Incorporated)
info@mito.org.nz if you wish to suggest changes to the content of this unit standard.
 New Zealand Qualifications Authority 2016