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Home >> Volkswagen >> 2000 >> Golf (1J1) L4-1.8L Turbo (AWD) >> 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







- VAG 1390 hand vacuum pump

Test requirements
- No DTCs in DTC memory.
- Output Diagnostic Test Mode (DTM) performed.
- No leaks in vacuum lines or hose connections
- Vacuum hoses not clogged or kinked

Test sequence







- Disconnect vacuum hose -1- at Secondary Air Injection (A1R) solenoid valve (N112) -2-.
- Connect VAG 1390 vacuum pump to vacuum hose -1-.


NOTES: Do not use pressurized air for the following test!







- Disconnect pressure hose -3- at Secondary Air Injection (AIR) pump and blow air in with light pressure (arrow).
Combination valve must close.
- Operate vacuum pump.
Valve must open.

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