ASE Compressed Natural Gas Vehicles (F1) Test — Information & Free Practice
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ASE Compressed Natural Gas Vehicles (F1) Test
- Provider
- ASE; computer-based delivery at Prometric test centers for initial F1 certification
- Format
- English multiple-choice knowledge examination; English-to-Spanish technical glossary available
- Exam questions
- Total questions: 65; Scored questions: 55; Unscored questions: 10; The total includes the scored and unscored questions.
- Time limit
- 90 minutes
Examination outline
Pre-Service Vehicle Inspection (9%)
- Vehicle integrity, alterations, emissions and safety standards
- Vehicle/system performance and needed actions
- Cylinder condition, expiration/end-of-life and shields/covers
- Cylinder and fuel-system component mounting
- Venting system location, condition and compliance
CNG System Equipment Inspection (15%)
- Fuel storage cylinders and system components
- Storage-system brackets, isolators, reinforcements and fasteners
- Regulator assemblies and coolant lines
- Underhood fuel delivery components
- System wiring
- Electrical and electronic components
- Fuel-system gauges
- Fuel lines, clamps, filters and fittings
- Valves, pressure-relief devices, venting, lines, fittings and fasteners
- Fuel fill receptacles and check valves
- Required labels
- Required system documentation
- Defueling receptacles
Leak Testing and Repairs (11%)
- Low- and high-pressure system leaks and repairs
- Cylinder pressurization with CNG
- Coolant leaks and repairs
- Venting-system integrity and repairs
Emissions and Performance Verification (20%)
- Regulator pressures and needed repair
- ECM/PCM calibration verification
- Electronic-component operation
- Fuel-gauge operation and repairs
- Emission tests, repairs and documentation
- Road testing, driveability and starting/restarting
- Manual and automatic bi-fuel changeover
- Abnormal fuel-system noises
- Gaseous fuel-management operation
System Diagnosis, Maintenance, and Repair (29%)
- Operational complaints and needed repair
- Visual gaseous-fuel component inspection and repairs
- DTC retrieval and interpretation using diagnostic equipment/scan tool
- Ignition-related driveability/emissions diagnosis and repair
- Fuel, air-induction and exhaust driveability/emissions diagnosis and repair
- Electronic engine-control driveability/emissions diagnosis and repair
- Vacuum/electrical/electronic operation and repair
- Gaseous-fuel delivery pressures, component operation and repair
- Fuel-line, valve, fitting and pressure-relief device replacement
- CNG system defueling
- Fuel contamination and fuel-filter inspection/replacement/service
General Cylinder Safety and Maintenance (16%)
- Visual cylinder, shield and mounting inspection
- Cylinder removal/replacement, recommended defueling and associated hardware
- Recommended cylinder handling and storage
- Cylinder-label interpretation and action
- Pressure-relief device and hardware inspection and action
- Cylinder/tank valve condition, operation and action
- Cylinder decommissioning using recommended procedures
Examination sources
- ASE F1 examination page
Study Guides, description and linked Compressed Natural Gas Vehicle Study Guide: Alt. Fuels CNG (F1)
- Official ASE F1 Study Guide
p. 3, Introduction, scope adoption
- Official ASE F1 Study Guide
p. 3, Introduction, Task List paragraph
- Official ASE F1 Study Guide
p. 4, Test Specifications and Task List, allocation table A-F and Total; headers and rows visually read
- Official ASE F1 Study Guide
p. 4, global safety note immediately before Task List A
- Official ASE F1 Study Guide
p. 5, Task List E, applicability note
- Official ASE F1 Study Guide
p. 3, How Long are the Tests?, F1 row, Number of Questions column
- Official ASE F1 Study Guide
p. 3, asterisk footnote beneath F1/F1R table
- Official ASE F1 Study Guide
p. 3, Introduction, sample-question formats paragraph
- ASE Certification: Need to Know
p. 3, step 3, question format and answer scoring
- Official ASE F1 Study Guide
p. 3, How Long are the Tests?, F1 row, Testing Time column
- ASE Certification: Need to Know
p. 3, How Do I Become Certified?, step 1
- ASE Certification: Need to Know
p. 4, What Are My Certification Options?, initial certification paragraph
- ASE Test Center Policies & Procedures
90 Days to Take Your Test
- ASE Test Center Policies & Procedures
Photo ID with Signature Policy
- ASE Work Experience Requirements
ASE Work Experience Requirements, testing before experience paragraph
- ASE FAQs
ASE Test Requirements, What is unique about the Advanced Level Tests (L1, L2, L3, and L4)?
Related license preparation
This examination may be required or accepted as an alternative, depending on the license and application pathway.