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Home >> Volkswagen >> 2004 >> GTI (1J1) L4-1.8L Turbo (AWP) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Overrun Shut-Off Valve, Checking >> With Manufacturer's Scan Tool
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With Manufacturer's Scan Tool



Overrun Shut-off Valve, Checking

Special tools and equipment







- VAG 1390 Hand vacuum pump

Test conditions
- Reduced performance or load change shudders

Test sequence

NOTE: The overrun shut-off valve is located in front of the turbocharger. It is opened by vacuum pressure during the overrun phase and at idling speed.







- Connect hand vacuum pump VAG 1390 to vacuum connection on overrun valve.
- Operate hand vacuum pump.

Overrun valve must open in direction of -arrow-.
- Operate vent valve on hand vacuum pump.

Overrun valve must close.
- If overrun valve does not open or close, replace valve.

NOTE: The overrun shut-off valve connections are secured with screw-type clips.
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