Volkswagen Workshop Service and Repair Manuals

Renewing vacuum unit for turbocharger   Note 10 mm hexagon socket -T10422 A- replaces the old 10 mm hexagon socket -T10422-. Existing keys without index »A« can still be used. However, 10 mm hexagon socket -T10422 A- must always be used for engine code CJAA. Special tools and workshop equipment required

t  10 mm hexagon socket -T10422- or 10 mm hexagon socket -T10422 A-

t  Ring spanner -T10423-

t  Hand vacuum pump -VAS 6213-

t  Open-end spanner, 14 mm -T10461- t  Vehicle diagnosis tester   Caution The special tools indicated, in particular 10 mm hexagon socket -T10422- or 10 mm hexagon socket -T10422 A-. are designed solely to be used in accordance with the following procedures and must not be used for other threaded connections. There is a danger of deformation if high torques are applied.   Note In order to change the vacuum unit with position sender for charge pressure positioner, -G581- a spare-parts kit is available → ETKA (Electronic parts catalogue). Removing –  Remove air filter housing with air mass meter and connecting pipe → Chapter.

–  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. Engine code CJAA.

–  Remove bolt -arrow- and remove hot air intake -1-. Continuation for all vehicles –  Pull off vacuum line at turbocharger.

–  Unscrew securing nut -arrow- where the oil supply line/vacuum line is connected to the cylinder head.   Caution When detaching the oil supply line, counterhold the connection. Risk of damage as a consequence!

–  Counterhold connecting pieces with open-end spanner -T10461- and unscrew oil supply line -arrow- from turbocharger. –  Seal oil supply opening in turbocharger with the plug from the spare-parts kit.

–  Counterhold lock nut -B- with ring spanner -T10423- and unscrew securing nut -A- from the control rod using 10 mm hexagon socket -T10422- or 10 mm hexagon socket -T10422 A-.

–  Unscrew securing bolts of the vacuum unit -arrows- and remove the vacuum unit -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 -A- and tighten fastening bolt.

–  Tighten securing bolts -arrows- to 8 Nm.   Note Make sure that the guiding element moves easily along the control rod. –  Connect hand vacuum pump -VAS 6213- to vacuum unit.   Note Because of its high degree of alloying, the securing nut is not magnetic. A magnet can be used for support.

–  Fit securing nut by hand -A-. –  Allow partial vacuum to escape from the vacuum unit. –  Remove protective cap, fit oil supply line to turbocharger and tighten to 22 Nm.

–  Connect connector -2- 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: –  Click the „01 - Engine electronics“ button on the display. The display indicates the control unit identification and the coding of the engine control unit. Select diagnostic function: –  Click the „011 - Measured values“ button on the display. –  Use the numeric keypad to enter the block of measured values „120“ and acknowledge entry with the „Q“ key. –  Connect hand vacuum pump -VAS 6213- to vacuum unit. –  Observe the lowest value of the measured value block and set a voltage of 0.760 V by causing a partial vacuum.   Caution During the following procedure for adjusting the control rod, keep the partial vacuum and thus the voltage of 0.760 V 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 -T10423-. –  Allow partial vacuum to escape from the vacuum unit. –  Observe the lowest value of the measured value block. When there is no pressure, the value should be 3.30 to 3.90 V. –  Fit 10 mm hexagon socket -T10422- or 10 mm hexagon socket -T10422 A-. Counterhold lock nut -B- with ring spanner -T10423- and tighten securing nut -A-.   Caution Cause a partial vacuum of 0.75 ± 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 0.760 V. 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 lock nut -B-, turn securing nut -A- in opposite direction and tighten it with 10 mm hexagon socket -T10422- or 10 mm hexagon socket -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

–  Fit securing nut -arrow- connecting the oil supply line/vacuum line to the cylinder head and tighten it. –  Remove sealing cap from turbocharger. –  Complete the engine. –  Start engine and delete event memory → Vehicle diagnostic tester. –  Check setting as follows: Select diagnostic function: –  Click the „006 - Basic setting“ button on the display. –  Use the numeric keypad to enter the block of measured values „120“ and acknowledge entry with the „Q“ key. –  Click the „Activate“ button in the lower half of the screen. –  Observe the value in the lower screen window; it must fluctuate between 0.65 ... 0.85 and 3.30 ... 3.90 V (vacuum unit is move to both end stops alternately). If voltage values OK: –  End basic setting procedure.