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Double Check-Valve, Checking






Double Check-Valve, Checking

The double-check valve has been discontinued as of 11.10.

Special tools, testers and auxiliary items required

Hand Vacuum Pump (VAS 6213)

Connector Test Set (V.A.G 1594 C)

Test Conditions:

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

Test Sequence:

Intake manifold overview. Refer to => [ Intake Manifold Overview ] Intake Manifold Overview.

- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.

- Disconnect the connector - 1 - and the ventilation hose - 3 - from the EVAP canister purge regulator valve 1 - 2 -.






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






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






- Connect the EVAP canister purge regulator valve 1 - 1 - contacts to the battery using the adapter cables from the connector test set (V.A.G 1594 C). This opens the EVAP canister purge regulator valve 1.

- Then activate the hand vacuum pump (VAS 6213) several times.

Vacuum must build up.

- Interrupt the voltage supply to the EVAP canister purge regulator valve 1.

No Vacuum:

- Replace the double check-valve - 2 - and the EVAP canister purge regulator valve 1 - 1 -.

The double check-valve, the EVAP canister purge regulator valve 1 and the plastic hoses are one component. The intake manifold must be removed to replace them.