AURLTF002
Diagnose and repair light vehicle diesel fuel injection systems


Application

This unit describes the performance outcomes required to diagnose and repair faults in the mechanically controlled diesel fuel injection systems of vehicles. It involves preparing for the task, selecting the correct diagnostic procedure, carrying out the diagnosis and the repair, performing post-repair testing, and completing workplace processes and documentation.

It applies to those working in the automotive service and repair industry. The diesel fuel injection systems include those in agricultural machinery, heavy commercial vehicles, light vehicles, marine vessels, mobile plant or outdoor power equipment. This unit does not apply to electronic compression ignition engine management systems.

No licensing, legislative, regulatory or certification requirements apply to this unit at the time of publication.


Elements and Performance Criteria

Elements

Elements describe the essential outcomes.

Performance Criteria

Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold and italicised text is used, further information is detailed in the range of conditions section.

1. Prepare to diagnose and repair diesel fuel injection system

1.1 Job requirements are determined from workplace instructions

1.2 Diagnostic information is sourced and interpreted

1.3 Diagnostic options are analysed and those most appropriate to the circumstances are selected

1.4 Hazards associated with the work are identified and risks are managed

1.5 Diagnostic tools and equipment are selected and checked for serviceability

2. Diagnose diesel fuel injection system

2.1 Engine tune adjustments are checked and rectified as required according to manufacturer specifications, workplace procedures, and safety and environmental requirements

2.2 Fuel system diagnostic tests are carried out according to manufacturer specifications, workplace procedures, and safety and environmental requirements

2.3 Faulty components are identified from diagnostic test results and causes of faults are determined

2.4 Diagnosis findings and recommendations for necessary repairs or adjustments are reported according to workplace procedures

3. Repair diesel fuel injection system

3.1 Repair information is sourced and interpreted

3.2 Repair options are analysed and those most appropriate to the circumstances are selected

3.3 Repair tools, equipment and materials are selected and checked

3.4 Repairs and component replacements and adjustments are carried out according to manufacturer specifications, safety and environmental requirements, and without causing damage to components or system

3.5 Post-repair testing is carried out according to workplace procedures to confirm fault rectification, and any further problems detected as having been introduced during the repair process are rectified

4. Complete work processes

4.1 Final inspection is made to ensure work is to workplace expectations and system or vehicle is presented ready for use

4.2 Work area is cleaned, waste and non-recyclable materials are disposed of, and recyclable material is collected

4.3 Tools and equipment are checked and stored according to workplace procedures

4.4 Workplace documentation is processed according to workplace procedures

Evidence of Performance

Before competency can be determined, individuals must demonstrate they can perform the following according to the standards defined in this unit’s elements, performance criteria, range of conditions and foundation skills:

diagnose and repair two different light vehicles with diesel engines, in which the work must involve:

removing, refitting and timing a diesel high pressure pump

removing, refitting and testing injectors

bleeding a diesel fuel injection system

removing and refitting a low pressure fuel pump.


Evidence of Knowledge

Individuals must be able to demonstrate knowledge of:

work health and safety (WHS) and occupational health and safety (OHS) requirements relating to diagnosing and repairing diesel fuel injection systems, including procedures for working with high pressure fuel systems

environmental requirements, including procedures for trapping, storing and disposing of fluids released from fuel injection systems

operating principles of diesel fuel injection systems and associated components, including:

phases of combustion

composition of diesel fuel, including cetane and sulphur content

application, purpose and operation of diesel fuel injection systems and components, including:

high pressure injection pump systems

distributor pumps, including axial and radial types

in-line injection pump systems

mechanically controlled unit type systems

testing procedures for diesel fuel injection systems, including procedures for:

assessing exhaust smoke

testing low fuel pressure pump

testing injector opening pressure and spray pattern

testing injector for back leakage and nozzle leakage

assessing and testing air induction system

assessing and testing engine performance

repair procedures for diesel fuel injection systems, including procedures for:

dismantling, cleaning, adjusting and reassembling conventional and two-spring injectors

removing, installing and timing high pressure injection pumps

bleeding fuel systems

post-repair testing procedures for diesel fuel injection systems, including assessing:

system leakage

engine performance.


Assessment Conditions

Assessors must satisfy NVR/AQTF assessor requirements.

Competency is to be assessed in the workplace or a simulated environment that accurately reflects performance in a real workplace setting.

Assessment must include direct observation of tasks.

Where assessment of competency includes third-party evidence, individuals must provide evidence that links them to the light vehicle diesel fuel injection systems that they have worked on, e.g. repair orders.

Assessors must verify performance evidence through questioning on skills and knowledge to ensure correct interpretation and application.

The following resources must be made available:

automotive repair workplace or simulated workplace

workplace instructions

manufacturer light vehicle diesel fuel injection specifications

two different light vehicles with diesel engines with faults

diagnostic equipment for diesel fuel injection systems

tools, equipment and materials appropriate for repairing diesel fuel injection systems.


Foundation Skills

This section describes those language, literacy, numeracy and employment skills that are essential to performance and are not explicit in the performance criteria.

Skills

Description

Learning skills to:

locate appropriate sources of information efficiently.

Reading skills to:

interpret information from manufacturer and workshop literature when seeking diesel fuel injection system specifications and procedures.

Writing skills to:

legibly and accurately fill out workplace documentation when reporting diagnostic findings, making repair recommendations, and recording parts and material used.

Oral communication skills to:

clarify instructions

report diagnostic findings and make repair recommendations.

Numeracy skills to:

measure diesel fuel injection system components and use basic mathematical operations, including addition and subtraction, to calculate distances, tolerances and deviations from manufacturer specifications.

Planning and organising skills to:

plan own work requirements and prioritise actions to achieve required outcomes and ensure tasks are completed within workplace timeframes.

Technology skills to:

use precision measuring equipment, including micrometers and dial indicator gauges.


Range Statement

This section specifies work environments and conditions that may affect performance. Essential operating conditions that may be present (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) are included. Bold italicised wording, if used in the performance criteria, is detailed below.

Safety and environmental requirements must include:

work health and safety (WHS) and occupational health and safety (OHS) requirements, including procedures for working with high pressure diesel fuel systems

environmental requirements, including procedures for trapping, storing and disposing of fluids released from fuel injection systems.


Sectors

Technical - Fuel Systems


Competency Field

Mechanical - Light Vehicle