Combination Valve, Checking
Combination Valve, Checking
The following procedure is used to test all combination valves.
Special tools, testers and auxiliary items required
• Hand vacuum pump (V.A.G 1390)
Test conditions
• Vacuum lines and hose connections free of leaks.
• Vacuum lines not plugged.
Test sequence
- Remove the vacuum hose from the combination valve.
- Connect hand vacuum pump (V.A.G 1390) to combination valve vacuum connection.
- Remove the air duct hose - arrow - from the Throttle Valve Control Module (J338) and position aside.
- 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.