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Checking intake manifold pressure sender G71 > < Checking charge pressure control solenoid valve N75

A4 Mk1

Checking linkage and vacuum unit for charge pressure control at turbocharger
Checking linkage and vacuum unit for charge pressure control at turbocharger
  Note
t  Problems with linkage/vacuum unit for charge pressure control result in the following faults:
t  Not achieving the specified charge pressure values.
t  Loss of power.
t  Uneven power delivery at part throttle
t  Jolts when throttle is opened or closed.
Special tools and workshop equipment required
   
t  Turbocharger tester -V.A.G 1397A-
  W00-0565
t  Hand vacuum pump -VAS 6213-
–  Check that all vacuum hoses have been fitted and are not leaking → Chapter.
  W00-10259
Procedure
–  Switch on turbocharger tester and set measuring range selector switch to position -I- (absolute pressure).
–  Attach test hose to connection -I-.
  V21-0096
–  Detach caps on engine cover panel.
–  Unbolt and remove engine cover panel -arrows-.
  A10-0202
–  Disconnect hose -arrow- from vacuum unit for charge pressure control.
  A21-0057
–  Connect hand vacuum pump -VAS 6213- or -V.A.G 1390- and turbocharger tester -V.A.G 1397A- using test hoses (as shown in illustration).
–  Operate vacuum pump.
–  Read the vacuum value on turbocharger tester -V.A.G 1397A-.
–  Also observe linkage at turbocharger.
l  Specification at 150 ± 20 mbar: linkage should start to move up.
l  Specification at 620 ± 20 mbar: linkage should make contact with upper stop.
If the specified values are not achieved or if the linkage does not move smoothly:
–  Renew turbocharger → Chapter.
  A21-0112

Checking intake manifold pressure sender G71 > < Checking charge pressure control solenoid valve N75