Volkswagen Workshop Service and Repair Manuals

Renewing vacuum unit for turbocharger   Note Hexagon key, extension 10 mm -T10422 A- repalces the old Hexagon key, extension 10 mm -T10422-. Existing keys without index »A« can still be used. Special tools and workshop equipment required

t  Hexagon key, extension 10 mm -T10422- or Hexagon key, extension 10 mm -T10422 A-

t  Ring spanner 10x12 -T10423-

t  Hand vacuum pump -VAS 6213- t  Vehicle diagnosis tester   Caution The special tools indicated, in particular the Hexagon key, extension 10 mm -T10422- or Hexagon key, extension 10 mm -T10422 A-is designed solely for use according to the following work instructions and must not be used for other threaded connections. There is a danger of deformation if high torques are applied.   Note In order to replace the vacuum unit with position sender for charge pressure positioner, -G581- a spare-parts kit is available → ETKA (Electronic parts catalogue). Removing

–  Open heat-protection mat and disconnect electrical connector -arrow- at position sender for charge pressure positioner -G581-.

–  Remove crankcase breather connecting pipe-1- from cylinder head cover; press release buttons to do this. –  Free vacuum hoses -arrows-. –  Unscrew bolt -2- (captive), swing air pipe with inlet connection to rear and pull off from turbocharger. –  Seal opening in turbocharger with the sealing cap from the spare-parts kit. –  Pull off vacuum line on the vacuum unit.

–  Counterhold lock nut -B- and unscrew securing nut -A- from the control rod with Hexagon key, extension 10 mm -T10422- or Hexagon key, extension 10 mm -T10422 A-.

–  Unscrew securing bolts of the vacuum unit -arrows- and remove the vacuum unit with position sender for charge pressure positioner -G581--A- Installing   Caution Only use new bolts and nuts from the spare-parts kit! –  If necessary, remove lower securing nut of the control rod from the new vacuum unit. –  Screw locknut by hand onto the control rod as far as possible in the direction of the vacuum unit.

–  Push control rod through the adjusting lever, fit vacuum unit with position sender for charge pressure positioner -G581--A- and tighten fastening bolts. –  Tighten securing bolts -arrows- to 8 Nm.   Note Make sure that the guiding element moves easily along the control rod.

–  Connect connector -arrow- to the position sender for the charge pressure positioner -G581- and close the heat protection mat. –  Connect vehicle diagnosis tester. Selecting operating mode: –  Click the „Vehicle self-diagnosis“ button on the display. Selecting vehicle system: –  Press button „01 - Engine electronics“ on display. The display shows the identification of the engine control unit. Select diagnostic function: –  Click the „011 - Measured values“ button on the display. –  In the selection list, select „Positioner for high pressure turbocharger, actual raw voltage“ and switch until measured value is displayed. –  Connect hand vacuum pump -VAS 6213- to vacuum unit. –  Set voltage of 760 mV by generating maximum 0.65 bar partial vacuum while observing the displayed measured value.   Caution During the following procedure for adjusting the control rod, keep the partial vacuum and thus the voltage of 760 mV constant.

–  Slowly screw the locknut-B- of the control rod downwards by hand. Adjusting lever is resting on the lower »stop«. –  Counterhold locknut-B- and screw securing nut-A- onto the control rod towards the adjusting lever. Tighten slightly with a ring spanner 10x12 -T10423-. –  Allow partial vacuum to escape from the vacuum unit. –  Observe displayed measured value; value at normal pressure should be set at 3000 … 3400 mV. –  Fit Hexagon key, extension 10 mm -T10422- or Hexagon key, extension 10 mm -T10422 A-, counterhold locknut -B- and tighten securing nut -A-.   Caution Cause a partial vacuum of 0.65 ± 0.05 bar to act on the vacuum unit in order to ensure that the adjusting lever rests against the »stop«. When this is done, the voltage should automatically be set to 760 mV. Voltage OK.

–  Press locking plate by hand onto the control rod and, if possible, turn 90° in the -direction of the arrow-. –  Seal connection between control rod and securing nut with sealing paint from the spare-parts kit. Voltage not OK.

–  Counterhold locknut -B-, undo securing nut -A- of the control rod and correct the voltage by turning the locknut -B-. –  Counterhold locknut -B-, turn securing nut -A- in opposing direction and tighten it with Hexagon key, extension 10 mm -T10422- or Hexagon key, extension 10 mm -T10422 A-.

–  Press locking plate by hand onto the control rod and, if possible, turn 90° in the -direction of the arrow-. –  Seal connection between control rod and securing nut with sealing paint from the spare-parts kit. Continuation –  Remove sealing cap from turbocharger. –  Complete the engine. –  Start motor and delete event memory → Vehicle diagnosis tester. –  Check setting as follows: Select diagnostic function: –  Click the „006 - Basic setting“ button on the display. –  Select „Adaption of turbocharger“ from selection list. –  Click the „Measured values“ button on the bottom right on the display. –  Select „Positioner for high pressure turbocharger, actual raw voltage“ from selection list. –  Click the „Start“ button on the bottom right on the display. –  Observe the value in the lower screen window; it must fluctuate between 650 ... 850 mV and 3,000 ... 3,400 mV (vacuum unit is move to both end stops alternately). If voltage values OK: –  End basic setting procedure.