Important: The GAP may only be performed by officially recognised vehicle workshops and responsible persons with the relevant training.
1. Preparatory work
Inspecting vehicle documents:
- Check whether the provided vehicle documents belong to the vehicle (compare vehicle ident. no. in vehicle documents to ident. no. on vehicle itself).
- Determine which gas is used to propel the vehicle that is being examined in order to ascertain that the necessary equipment is available
- Ensure that the tank modules are filled to at least 50% (max. 75% - tank gauge approx. 3/4) with fuel. No additional checking is required if the prescribed filling quantity is exceeded.
2. Implementation
Component Identification and Visual Inspection
Component identification ensures that only prescribed and properly marked gas system components are used. At the same time, all gas system components must be subjected to a visual inspection. The visual inspection is used to check the condition (damage, corrosion, attachment) of the gas system, provided that this can be done without dismantling.
Activity
Identification and Visual Inspection
This includes:
- Tank modules
- Pressure controllers/reducing valves
- High/low pressure lines
- Safety-related components such as:
- Service life of gas container(s) (tank module(s))
- Attaching the tank modules
- Tank fittings
- Module safety valves
- Gas tank filler valve
- Discharge devices
- All gas-carrying low/high pressure lines
- All threaded line connections of the gas-carrying high/low pressure lines
- Pressure controllers/reducing valves
- Gas injection valves
- Warning and indicator lamps
- All other relevant gas system components
Visually Inspect Whether the Components Are:
- kinked
- damaged
- corroded
- loose
- chafing on parts of the body because of vibration when driving
2.1 Function Check
Activity
The operation of the following components must be checked:
- Main shutoff valve at each tank module
- Gas/petrol operation fuel switch
- Control equipment/start inhibit
Note. Extreme care must be taken when closing the shutoff spindles. Additional torque because of cylinder pressure. Do not use excessive force.
3. Leak Test
Activity
As a prerequisite for the test the tank modules must be full to at least 50% with fuel. No additional checking is required if the prescribed filling quantity is exceeded.
Note. If the check cannot be carried out with the engine running, allow engine to run for at least 2 minutes in "gas mode" and perform leak test immediately after switching off the engine.
The leak test must be carried out using a leak detection device or a leak detection spray. If gas emissions are detected with the leak detection device, a leak detection spray must also be used to find the leaking connection or component. All lines, connections and components that may possibly be leaking must be sprayed. The acting time of the leak detection spray must be at least 3 minutes. The gas system can be considered to be free of leaks if no bubbles become visible within the 3-minute acting time of the leak detection spray.
Component leak testing:
- Set fuel switch to "gas mode" (only if operating in "fuel mode").
- Start engine and allow to run
- Perform leak test of the high and low pressure system using the leak detection device or leak detection spray. All threaded connections of the high-pressure lines and all high and low pressure lines, engine supply lines, valves, pressure controllers and reducing valves and all other relevant gas system components must be checked using the leak detection device or leak detection spray.
Warning: Vehicles in which gas system leaks are detected must not be handed over to customers for safety reasons. Any leaks that are detected must be remedied quickly and properly.
4. Test Certificate for Vehicle Owner
Activity
Create test certificate
- When the gas system check is complete, the person responsible must produce a test certificate
- The test certificate must be handed to the vehicle owner
- If no problems are found, this fact must be noted in the test certificate
- If problems are found they must be noted in the test certificate. The deficiencies must be remedied immediately. The vehicle must be subjected to another gas system check within one month if the deficiencies cannot be remedied immediately. The test certificate must be presented.
- The test certificate must be retained for 3 years.
Test Certificate
Note. The test certificate for the gas system check must contain the following information
- 1. Company that performed the check (company stamp)
- 2. Date of gas system check
- 3. Initial registration date of vehicle
- 4. Type and model of vehicle and key number
- 5. Vehicle manufacturer and key number for 2
- 6. Vehicle type and key number
- 7. Vehicle identification number
- 8. Type of gas system
- 9. Reason for check
- 10. Result of visual inspection
- 11. Result of function check
- 12. Result of leak test
- 13. Overall result of gas system check
- 14. The date and the signature of the person responsible for the gas system check, the control number of the recognised workshop and the verification seal with stamp number or the signature of the person responsible for carrying out the gas system check, together with test stamp and identification number.
5. Ece Regulation/stvzo
- 1. ECE R110 (drive system with compressed natural gas)
- 2. § 41a of the StVZO (ECE R110 requirements were transferred to § 41a)
Note. The gas system testing interval corresponds with the main inspection interval. The first check must take place after 3 years, and every 2 years thereafter. Regular gas system checking is an independent constituent of the main inspection (similar to the emissions test). The gas system check must always be carried out by a responsible person who is commissioned to do so or by an expert under the supervision of a responsible person or in an officially recognised monitoring organisation by test engineers (PI) or motor vehicle traffic testers (aaSPO).
6. General Safety Regulations for Cng-Operated Vehicles
The general safety regulations pertaining to CNG-operated vehicles must be complied with
Sectional Diagrams with Components
Astra-G Cng
- 1. CNG pressure reducing valve
- 2. CNG low pressure line
- 3. CNG distribution pipe (CNG injection valves)
- 4. Switch for gas/petrol operation
- 5. Voltage converter, CNG engine control unit (vehicles with chassis number W0L0TGT 3542057902 only)
- 6. CNG tank filler valve
- 7. CNG tank filler valve line
- 8. CNG tank module, rear
- 9. CNG module safety valve, rear
- 10. CNG high-pressure line between the CNG tank modules
- 11. CNG module safety valve, front
- 12. CNG high pressure line, rear
- 13. CNG high pressure line, centre / CNG high pressure line, rear connector
- 14. CNG tank module, front
- 15. CNG high pressure line, centre
- 16. CNG discharge connection or CNG connection in the version without a CNG discharge connection
- 17. CNG high pressure line, front
- 18. Discharge hose, CNG pressure reducing valve
Corsa-C Combo Cng
- 1. CNG distribution pipe (CNG injection valves)
- 2. CNG low pressure line
- 3. Discharge hose, CNG pressure reducing valve
- 4. Switch for gas/petrol operation
- 5. CNG tank module, front
- 6. CNG tank filler valve line
- 7. CNG tank filler valve
- 8. CNG module safety valve, centre
- 9. CNG tank module, rear
- 10. CNG tank module, centre
- 11. CNG module safety valve, rear
- 12. CNG high-pressure line between the rear and centre CNG tank modules
- 13. CNG high pressure line between the front and rear CNG tank modules
- 14. CNG module safety valve, front
- 15. CNG high pressure line, CNG tank module, front
- 16. CNG high pressure line, centre / CNG high pressure line, rear connector
- 17. CNG high pressure line, centre
- 18. CNG discharge connection or CNG connection in the version without a CNG discharge connection
- 19. CNG high pressure line, front
- 20. CNG pressure reducing valve
Zafira-A Cng
- 1. Pressure reducing valve
- 2. CNG low pressure line
- 3. CNG distribution pipe (CNG injection valves)
- 4. Voltage converter, CNG engine control unit (vehicles with chassis number W0L0TGT 7542057677 only)
- 5. Switch for gas/petrol operation
- 6. CNG tank filler valve
- 7. CNG filling line
- 8. CNG tank module, rear
- 9. High-pressure line, module safety valve
- 10. Safety module valve (CNG tank module, rear)
- 11. High pressure line, front/rear CNG tank modules
- 12. High-pressure line, module safety valve
- 13. Safety module valve (CNG tank module, front)
- 14. CNG high pressure line, rear
- 15. Separation point/threaded pipe connection
- 16. CNG high pressure line, centre
- 17. CNG tank module, front
- 18. CNG discharge connection or CNG connection in the version without a CNG discharge connection
- 19. CNG high pressure line, front
Zafira-B Cng
- 1. Pressure reducing valve
- 2. CNG low pressure line
- 3. Discharge hose, CNG pressure reducing valve
- 4. CNG high pressure line, front
- 5. Switch for gas/petrol operation
- 6. CNG tank module, front
- 7. CNG tank filler valve
- 8. CNG filling line
- 9. CNG tank module, rear
- 10. Safety module valves (CNG tank module, rear)
- 11. High pressure line between front and rear tank modules (CNG tank module, rear)
- 12. High pressure line between front and rear CNG tank modules
- 13. Safety module valves (CNG tank module, front)
- 14. High pressure line between front and rear tank modules (CNG tank module, front)
- 15. High pressure line between front tank module (CNG tank module, front) and centre CNG high pressure line
- 16. Separation point/threaded pipe connection
- 17. CNG high pressure line, centre
- 18. CNG discharge connection or CNG connection in the version without a CNG discharge connection
- 19. CNG distribution pipe (CNG injection valves)
1
) Put a cross next to applicable items