volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

ABOUT US
Removing and installing injectors > < Installing

Golf Mk4

Dynamically checking and adjusting commencement of injection
Dynamically checking and adjusting commencement of injection
  Note
t  Dynamically checking and correcting commencement of injection is only possible in function 04 “Engine basic setting”.
t  Commencement of injection must always be checked, and if necessary adjusted, after renewing the toothed belt or loosening the injection pump bolts or toothed belt pulleys.
Special tools and workshop equipment required
   
t  Torque wrench -V.A.G 1331-
  W00-0427
t  Fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552-
  W00-0459
t  Diagnosis cable -V.A.G 1551/3-
Test and adjustment prerequisites
l  Mechanical engine basic setting OK.
l  Toothed belt tension OK.
Procedure
–  Connect fault reader -V.A.G 1551- or vehicle system tester -V.A.G 1552- and select engine electronics control unit with “address word” 01. Engine must be idling. (Connecting fault reader and selecting engine electronics control unit → Chapter.)
  W00-0047
Indicated on display:
–  Press buttons 0 and 4 for function “Initiate basic settings” and confirm entry with Q button.
  
Rapid data transfer                 HELP
Select function XX
Indicated on display:
–  Press button 0 three times for “Display group number 0” and confirm entry with Q button.
  
Basic setting                       HELP
Input display group number XXX
Indicated on display: (1...10 = display zones)
–  Check coolant temperature in display zone 7.
Specification: Less than 73 (corresponds to 85°C)
Continue with check only if coolant temperature is achieved.
Engine codes AGR, AHF, ALH, ASV
Commencement of injection in display zone 2 is dependant on fuel temperature in display zone 9.
  
System in basic setting 0            ->
  1   2   3   4   5   6   7   8   9  10
A - display zone 2 commencement of injection B - display zone 9 fuel temperature C - specified value range for commencement of injection
Example
Numerical value 90 in display zone 9 -B- corresponds to a numerical value range of 34..73 in display zone 2 -A-.
Engine codes AGP, AQM
  N23-0260
A - display zone 2 commencement of injection B - display zone 9 fuel temperature C - specified value range for commencement of injection
Example
Numerical value 90 in display zone 9 -B- corresponds to a numerical value range of 25..78 in display zone 2 -A-.
Continuation for all engine codes
  Note
If, when checking the commencement of injection, the specifications are within zone -C- then no readjustment is required. After repairs, e.g. removing and installing injection pump, adjusting timing, the commencement of injection must be set to the mean valve (dashed line) of specification zone -C-.
If the commencement of injection lies outside of the specification range, adjust commencement of injection as follows:
Engine codes AGR, AHF, ALH, ASV
–  Remove connecting pipe between charge air cooler and intake manifold.
Continuation for all engine codes
–  Remove upper toothed belt guard.
  N23-0318
–  Loosen two securing bolts -1- for injection pump sprocket.
–  To hold pump shaft, place a 22 mm ring spanner on hub nut -2-.
–  Loosen third injection pump sprocket securing bolt and turn pump shaft slightly:
To the left = commencement of injection later
To the right = commencement of injection earlier
  Note
On no account must the nut -2- for the hub be loosened. Otherwise the injection pump basic setting may be altered and this cannot be reset with normal workshop equipment
  A23-0044
Type -A-: securing bolts with milled neck and tapered end -arrow-
–  Tighten new securing bolts of injection pump belt pulley. Specified torque: 20 Nm.
  Note
t  Following dynamic check of commencement of injection, securing bolts should be tightened further by 90° (1/4 turn).
t  The securing bolts should only be used once as these are stretch bolts.
Type -B-: securing bolts without milled neck and with flat end
–  Tighten old securing bolts of injection pump belt pulley.
Specified torque: 25 Nm.
  Note
Do not renew securing bolts.
Continuation for all versions
–  Observe figures in zone 2 and if necessary adjust again until the mean value for specified range -C- is displayed.
  N13-0614
Type -A-: securing bolts with milled neck and tapered end -arrow-
–  Tighten new injection pump sprocket securing bolts 1/4 turn (90°) further.
Continuation for all versions
–  Press → button.
–  Press buttons 0 and 6 for function “End output” and confirm entry with Q button.
–  Switch off ignition.
Engine codes AGR, AHF, ALH, ASV
–  Install connecting pipe between charge air cooler and intake manifold.
Continuation for all engine codes
–  Fit upper section of toothed belt guard.
  N13-0614

Removing and installing injectors > < Installing