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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 >> Deceleration Shut-Off Valve, Checking >> With Generic Scan Tool
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With Generic Scan Tool



Deceleration shut-off valve, checking

Recommended special tools and equipment
e.g.:







- VAG1390 hand vacuum pump

Test requirement
- Performance deficiency or tip-in shocks

Test sequence

NOTE: The deceleration shut-off valve is located in front of the turbocharger. It is opened by vacuum during deceleration and at idle.







- Connect hand vacuum pump (VAG1390) to vacuum connection for deceleration shut-off valve.
- Operate vacuum pump.
Deceleration shut-off valve must open in direction of arrow

- Operate ventilation valve at vacuum pump.
Deceleration shut-off valve must close

If deceleration shut-off valve does not open or does not close, replace valve.

NOTE: Secure connections of deceleration valve using screw-type clamps.