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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.