Audi AMB Service Manual page 607

ENGINE 1.8 Liter 4-Cyl. 5V Turbo Engine Mechanical, Engine Code(s): AMB
Installed position: Arrow on valve points in direction of flow, as shown in illustration
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21 - Secondary Air Injection (AIR) Solenoid Valve N112
Component location: Below intake manifold
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22 - Charge air cooler
With Charge Air Pressure Sensor G31
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23 - Recirculating valve for turbocharger N249
Component location: Below intake manifold
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24 - Vacuum diaphragm for boost pressure regulation
When combination valve is opened, mechanical boost pressure regulation valve in turbocharger is opened
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and secondary air is thereby channeled past turbocharger directly to catalytic converter
Turbocharger and charge pressure control valve, checking
Special tools, testers and auxiliary items required
Fig. 290: Identifying Turbocharger Tester V.A.G 1397 A
Courtesy of VOLKSWAGEN UNITED STATES, INC.
Turbocharger tester VAG1397A
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2005 Audi A4 Quattro
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