Audi AMB Service Manual page 619

ENGINE 1.8 Liter 4-Cyl. 5V Turbo Engine Mechanical, Engine Code(s): AMB
Vacuum hand pump VAG1390
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Work sequence
Fig. 304: Connecting Hand Vacuum Pump V.A.G 1390 To Vacuum Connection Of Charge Pressure
Bypass Valve
Courtesy of VOLKSWAGEN UNITED STATES, INC.
Connect vacuum pump VAG1390 to air recirculation valve.
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Operate vacuum hand pump.
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Air recirculation valve should open - arrow -.
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Operate air vent valve on vacuum pump after approx. 30 seconds.
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Air recirculation valve should close - arrow -.
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If the mechanical air recirculation valve does not open and close as specified, or if the valve plate does not seal
properly when the valve is closed:
Replace mechanical air recirculation valve and secure hose connections with hose clamps.
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Recirculating valve for turbocharger N249 , checking
2005 Audi A4 Quattro
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