Audi Workshop Service and Repair Manuals

Notes:

• ◆ The commencement of injection must always be checked after renewing the toothed belt or loosening the injection pump bolts or toothed belt sprockets and if necessary adjusted.
• ◆ Dynamically checking and correcting commencement of injection is only possible in function 04 "Engine basic setting". This is because in function 04 the commencement of injection valve is activated continuously and therefore the injection timing control is set to "late" (retarded).

• ‒ Initiate basic setting, Display Group 00, engine at idling speed
  .

• ‒ Monitor the display in display zone 7 (coolant temperature).

• Specification: less than 73 (corresponds to 85°C)

Do not continue with the test until the coolant has reached the specified temperature.

• ‒ → The commencement of injection value in display zone 2 varies in accordance with the fuel temperature value in display zone 9.

• Specification: => range C in illustration
• A - Zone 2 commencement of injection
• B - Zone 9 fuel temperature

Notes:

• ◆ If the commencement of injection is advanced turn injection pump in engine direction of rotation, if the commencement of injection is retarded turn against direction of rotation.
• ◆ If when checking the commencement of injection the specifications are within zone -C- then no adjustment is required. After repairs e.g. removing and installing injection pump, adjusting timing then the commencement of injection is to be set to the mean valve (dashed line) of specification zone -C-.

If the commencement of injection (timing) is outside the specification tolerances, adjust commencement of injection as follows:

Adjusting commencement of injection

• ‒ Remove upper toothed belt guard, if it has not already been removed.
• ‒ Loosen injection pump securing bolts approx. one turn, leaving the easiest bolt to reach till last.

• ‒ Hold injection pump by hand under tension in direction to be adjusted.
• ‒ Carefully loosen last securing bolt until the pump can be turned slightly and then retighten securing bolt.
• ‒ Check setting in function "Basic setting 04".

• ‒ Observe readout in display zone 2 and if necessary adjust again until the readout settles on the mean value shown in specification range -C-.
• ‒ Tighten injection pump securing bolts to 25 Nm.
• ‒ Check commencement of injection again.

Note:

Loosen and re-tighten (25 Nm) the injection pipes on the injection pump after dynamically adjusting the injection pump. This relieves the strain on pipes and prevents vibration breakages.