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Home >> Volkswagen >> 2004 >> Passat Sedan (3B3) L4-1.8L Turbo (AWM) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Combination Valve, Checking
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Combination Valve, Checking



Combination Valve, Checking

Recommended Special Tools And Equipment








- VAG1390 hand vacuum pump

Test requirements
- No leaks in vacuum lines or hose connections.
- Vacuum hoses not clogged or kinked
- Pressure hose for Secondary Air Injection (AIR) Pump Motor not clogged or kinked

Test sequence







- Disconnect vacuum hose at combination valve (arrow) and connect the hand vacuum pump (VAG1390).

NOTE: Do not use pressurized air for the following test.







- Disconnect pressure hose (arrow) at Secondary Air Injection (AIR) pump motor and blow air in with light pressure.
Combination valve must close.
- Operate vacuum pump.
Valve must open.

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