Start of Injection, Dynamically Checking and Adjusting
Special Tools, Testers And Auxiliary Items:- VAG 1551/1552 Scan Tool with VAG 1551/3 adaptor cable
- 3035 Tubing wrench
- VAG 1331 Torque wrench 5 to 50 Nm (3.7 to 37 ft lb)
NOTES:
- Dynamically checking and correcting start of injection is only possible in Function 04 "Engine basic setting"
- start of injection must always be checked/adjusted after:
+ replacing toothed belt
+ loosening Diesel Injection pump bolts
+ loosening toothed belt sprockets
Checking and Adjustment Conditions:
- Mechanical engine basic setting OK
- Toothed belt tension OK
- Connect VAG 1551/1552 Scan Tool
- Start engine and let idle
- Press 0 and 1 buttons to select address word 01 "engine electronics"
Display will appear as shown:
Rapid data transfer HELP
select function XX
- Press 0 and 4 buttons to select Function 04 "basic setting"
- Press Q button to enter input
Display will appear as shown:
Basic setting HELP
input display group number XX
- Press 0 button three times to select display group 0
- Press Q button to enter input
Display will appear as shown (1 to 10 = Display zones):
System in basic setting 0 ->
1 2 3 4 5 6 7 8 9 10
NOTE: The start of injection in display zone 2 is dependent on the fuel temperature in display zone 9.
A. Display zone 2 start of injection
B. Display zone 9 fuel temperature
C Specified range for start of injection
Example: The value 90 in display zone 9 (B) corresponds to a numerical value range of 34 to 73 in display zone 2 (A).
NOTES:
- If start of injection is advanced; turn injection pump in direction of engine direction, if start of injection is retarded turn against direction of rotation.
- If when checking the start of injection the specifications are within zone -C-; no adjustment is required. After repairs e.g. removing and installing injection pump, set the start of injection to the mean value (dashed line) of spec. zone -C-.
- Loosen injection pump mounting bolts approx. one turn, leaving the easiest bolt to reach until last
- Hand hold injection pump under tension in direction to be adjusted
- Carefully loosen last mounting bolt until the pump can be turned slightly and then retighten mounting bolt
- Observe figures in zone 2 and if necessary adjust again until the mean value for specification zone -C- is displayed
- Tighten injection pump mounting bolts
- 25 Nm (18 ft lb)
- Check start of injection again
- Press -> button
- Press 0 and 6 buttons to select Function 06 "end data transfer"
- Press Q button to enter input
NOTE: Loosen and re-tighten 25 Nm (18 ft lb) the injector lines on the injection pump after it has been dynamically adjusted. This relieves any line strain and prevents damage due to vibration.