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Home >> Volkswagen >> 2000 >> Passat Sedan (3B2) L4-1.8L Turbo (ATW) >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Air Injection >> Testing and Inspection >> Combination Valve, Checking
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Combination Valve, Checking



Special tools and equipment





- V.A.G 1390 Hand vacuum pump

Checking conditions
- No code stored in Diagnostic Trouble Cede (DTC) memory.
Testing and Inspection
- Perform Output Diagnostic Test Mode (DTM).
Testing and Inspection
- Vacuum lines and hose connections free of leaks.
- Vacuum lines not blocked/kinked.

Checking sequence







- Pull vacuum hose off combination valve (arrow) and connect hand vacuum pump V.A.G 1390.


NOTES: Do not use compressed air during the following deck!







- Remove pressure hose from secondary air injection pump motor and blow into hose lightly.
- Combination valve must be closed.
- Operate hand vacuum pump.
- Combination valve must open.

If the combination valve does not open:
- Replace combination valve

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