Audi Workshop Service and Repair Manuals

Test requirements:

• ● Engine must be idling.
• ● Vehicle diagnostic, testing and information system VAS 5051 connected; vehicle self-diagnosis and vehicle system "01 - Engine electronics" selected

Test sequence

• ‒ → Pull dipstick -1- out of guide tube.
• ‒ Unclipcaps.
• ‒ Remove nuts -arrows- and detach engine cover.
• ‒ Remove insulation lying below.
• ‒ Re-insert dipstick into guide tube.

• ‒ → Screw out bolts -arrows-.
• ‒ Remove air duct -1- and -2-.

• ‒ → Detach hose -arrow- from charge pressure control vacuum unit.

• ‒ → Switch on turbocharger tester and set range switch to position -I- (absolute pressure).
• ‒ Attach measurement hose to connection -I-.
• ‒ Connect measurement hose to detached vacuum hose.

→ Readout on VAS 5051:

• ‒ Enter diagnostic function "04 - Basic setting" in selection -1-.

→ Readout on VAS 5051:

•     1 -    Enter display group
  max. input value = 255

• ‒ Use keypad-2- to enter "033" for "Display group number 033" and confirm by touching Q key.
• ‒ The idle speed is increased to 1400 rpm
• ‒ The charge pressure control vacuum unit is actuated at intervals

• ‒ → Specification on V.A.G 1397 A:
  Greater than 650 mbar on actuation of vacuum unit

Note:

The absolute pressure indicated on the V.A.G 1397 A must fall by the specified amounts.

If reading does not match specification:

• ‒ Check whether charge pressure control hose has dropped off or is clogged => Page 21-24.
• ‒ Check charge pressure control solenoid valve -N75 => Page 21-26.

If vacuum does not drop when actuation finishes:

• ‒ Check vent lines => Page 21-24.
• ‒ End function "04 - Basic setting" by pressing ◂ key.

→ Readout on VAS 5051:

• ‒ Enter diagnostic function "06 - End output" in selection -1-.