Combination Valve for Secondary Air Injection (AIR), checking function and proper seal

The following procedure is used to test all combination valves.

Special tools, testers and auxiliary items required 

• Hand vacuum pump.

Test conditions 

• Vacuum lines and hose connections free of leaks.
• Vacuum lines not plugged.

Test sequence 

• Remove the vacuum hose from the combination valve.

Fig 1: Hand Vacuum Pump V.A.G 1390 Connected To Combination Valve Vacuum Connection

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• Connect hand vacuum pump V.A.G 1390 to combination valve vacuum connection.

Fig 2: Identifying Air Duct Hose

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• Remove the air duct hose - arrow  - from the Throttle Valve Control Module J338 and position aside.

Fig 3: Identifying Secondary Air Injection Hose

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• Disconnect the Secondary Air Injection hose - arrow  -.
• Inject a light air pressure into the in Secondary Air Injection hose to close the combination valve. (do not use compressed air).

• The combination valve should close and seal. Air should not be able to pass through the combination valve.

• Operate the hand vacuum pump.

• The combination valve should open. Air should be able to pass through the combination valve.

If combination valve does not open:

• Replace the faulty combination valve. Refer to 26 EXHAUST SYSTEM, EMISSION CONTROLS .

End of procedure