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Home >> Audi >> 2004 >> TT Roadster (8N9) L4-1.8L Turbo (AWP) >> 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.
- Connect hand vacuum pump (VAG1390) to vacuum hose of combination valve.

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

- Disconnect pressure hose between Secondary Air Injection (AIR) Pump Motor and connecting pipe and blow into it with light pressure.
Combination valve must close.
- Operate hand vacuum pump.
Combination valve must open.

If the combination valve does not open or it is constantly open:
- Replace combination valve.
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