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Testing start of injection valve > < Testing fuel injection control

A4 Mk1

#Diesel direct injection and glow #plug system (4-cyl.)>06.97
Testing fuel injection control
Testing injection timing device
 
→ Perform final control diagnosis and actuate start of injection valve => Page .
Final control diagnosis    ⇒
Start of injection valve- N108

When start of injection valve is actuated, a distinct change in combustion noise must be heard (injection timing device fluctuates between "late" and "early").
 
→ Initiate basic setting (function 04) and select display group 00 => Page .
Basic setting 0    ⇒
40    46    0    20    90    201    64    153    127    83
  • ‒ Correct start of injection if necessary .
  • ‒ Pull out fuse for engine electronics in E-box.
  • ‒ Observe reading in display field 2.
    		•
     
    → Reading in display field 2 must run up to 255.
    Basic setting 0    ⇒
    40    255    0    20    90    201    64    153    127    83

    Note:

    The break in voltage causes the start of injection valve to close. The internal pump pressure can no longer be reduced and acts in full on the timing device plunger. The timing device moves to the "early" stop.

    • ‒ If desired value is not attained, timing device is blocked in injection pump and injection pump must be replaced.
    • ‒ Interrogate and erase fault memory. Several faults may have been stored as a result of pulling out the fuse.

    Testing start of injection valve > < Testing fuel injection control