Combination Valve for Secondary Air Injection (air), Checking Function and Proper Seal Audi TT 8N

The following procedure is used to test all combination valves.

Special tools, testers and auxiliary items required

1. Hand vacuum pump

Test conditions

1. Vacuum lines and hose connections free of leaks.
2. Vacuum lines not plugged.

Test procedure

1. Perform a preliminary check to verify the customers complaint. Refer to --> «General Diagnosis»(ref-276276-S40851803372008010300000) .

Start diagnosis

1. Remove the vacuum hose from the combination valve.

Scheme 48

1. Connect the hand vacuum pump to combination valve vacuum connection.

Scheme 49

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

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

1. Operate the hand vacuum pump.

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

If combination valve does not open

1. Replace the faulty combination valve. Refer to --> «26 EXHAUST SYSTEM, EMISSION CONTROLS»(ref-276269-S01656351712008010300000)

End of procedure.