Volkswagen Workshop Service and Repair Manuals

Notes:

• ◆ The work sequence is dependent upon the programme level of the Digifant control unit. Programme level number , connecting fault reader V.A.G 1551 and selecting engine electronics control unit.
  
• ◆ The following check checks the overrun cut-off. If this check is OK., then the acceleration and full load enrichment are also OK.

• ‒ Connect fault reader V.A.G 1551 and select engine electronics control unit (address word 01); selection is carried out with engine idling.
  => Page 01-3

• ‒ Input 08 for "Read measured value block" function and confirm with Q.

• ‒ Input 01 for display group 01 and confirm with Q.

Note:

If something different is indicated on the display:

=> Fault reader operating instructions

Do not continue with test until

• ● The coolant temperature is above 85 °C
  -display zone 1-
• ● The engine has then run for a further 2 minutes at idling speed

• ‒ Note figure in display zone 4.
• ‒ Increase engine speed by revving up to at least 3000 rpm (see display zone 2) and release accelerator. The displayed figure in display zone 4 (injection period) must
       increase, drop back to 0 ms and rise again to the noted figure.
• ‒ Press ⇒ button.
• ‒ Input 06 for "End output" and confirm with Q.

If the displayed figure does not increase and does not drop back to 0 ms:

• ‒ Carry out idling check => Page 24-25 .
• ‒ Check throttle valve potentiometer => Page 24-39 .