Testing Requirements

Check Diagnostic Trouble Code (DTC) memory and carry out Output Diagnostic Test Mode (DTM). See OUTPUT DIAGNOSTIC TEST MODES (DTM) in SELF-DIAGNOSTICS article.
Engine oil temperature at least 86°F (30°C).
Ensure no leaking vacuum connections.
Turn quick fasteners on connector cover on rear engine compartment bulkhead 90 degrees to left and remove cover. See Fig 1.
Disconnect moisture separator 1 from bracket 2 and pull off hose 3. Fit T-piece with measuring hose of turbocharger tester between moisture separator 1 and disconnected hose. See Fig 2.
Route measuring hose over rear edge of hood and through right window opening into vehicle interior.
Switch on turbocharger tester, switch measuring range switch to position 1 and attach measuring hose to union 1. Note the following when using the turbocharger tester:
Hoses must be connected absolutely leak free, as otherwise measuring errors are possible.
By pressing memory button M on turbocharger tester, the last measuring value is stored until the memory button M is pressed again or the tester is switched OFF. See Fig 3.
Storage in memory is indicated by blinking of the decimal point in the display.
If battery voltage of the turbocharger tester drops below the permissible limit, an arrow appears in upper left-hand corner of the display.
Before checking, drive the vehicle briskly for at least 2 miles with no traffic lights, etc.
As boost pressure is measured during driving, a second mechanic must be present to operate the turbocharger tester for safety reasons.

Fig 1: Location Of Fasteners On Vacuum Connector Cover.

Courtesy of AUDI OF AMERICA, INC.

Fig 2: Identifying Turbocharger Tester Vacuum Connection Location

Courtesy of AUDI OF AMERICA, INC.

Fig 3: Identifying Turbocharger Tester

Courtesy of AUDI OF AMERICA, INC.