Fuel Rail: Testing and Inspection

Double Check-Valve, Checking

Special tools, testers and auxiliary items required

• Hand Vacuum Pump (VAS 6213)

• Connector Test Set (V.A.G 1594C)

Test Conditions

• The Evaporative Emission (EVAP) canister purge regulator valve 1 (N80) was tested with the vehicle diagnostic tester and is OK.

- Remove the engine cover.

- Disconnect the connector - 1 - and the ventilation hose - arrow - from the EVAP canister purge regulator valve.






- Set the slide ring - 1 - on the (VAS 6213) to the -A- position for "vacuum."






- Connect the (VAS 6213) to the EVAP canister purge regulator valve 1.






- Using the lines, connect the contacts on the EVAP canister purge regulator valve 1 - 1 - to the battery. This opens the EVAP canister purge regulator valve 1.

Then activate the (VAS 6213) several times.

• Vacuum must build up.

- Disconnect the battery again (interrupt the power supply).

No vacuum

- Replace the double check-valve - 1 -.

The double check-valve, the EVAP canister purge regulator valve 1 and the plastic hoses are a single component and can only be replaced together.