TorqFix

Checking air recirculation valve for turbocharger N249 - vehicles with electronic throttle — AUDI

Checking air recirculation valve for turbocharger N249 - vehicles with electronic throttle on Audi: 36 steps, engines AGU, AJQ, APP, AQA.

Workshop procedure for AUDI — the exact step sequence and torque figures, straight from real workshop data.

36 steps 27 engine codes

🧭 Before you start

Fits: Audi A3 (8L, 1996–2003)

Don't miss

  • Turbocharger air recirculation valve N249 is supplied with power via fuel pump relay J17.
  • Connect adapter cableV.A.G 1598/31 (test box) to connectors of wiring harness; do not connect engine control unit. Connect earth clip of test box to earth (arrow)24.
  • Secure all hose connections with the correct type of hose clips (same as original equipment) Parts catalogue.

📋 Procedure

  1. Connect up vehicle diagnostic, testing and information systemVAS 5051 with diagnosis leadVAS 5051/1, press vehicle self-diagnosis key and select vehicle system "“01 - Engine electronics”". When doing this, the engine must be running at idling speed.
  2. From list (1), select diagnosis function "“02 - Interrogate fault memory”".
  3. Terminate function "“02 - Interrogate fault memory”" by touching ← key.
  4. Press function "“06 - end output”" and switch off the ignition.
  5. Take off engine cover panel (arrows).
AGU? Steps differ between engine variants — check this job against your exact car before you commit to it. Check my car — free →
  1. Remove cover in front of intake manifold (arrows).
  2. Detach pipe for secondary air system from brackets on engine (arrows).
  3. Remove bolts (2) and (3) and detach bracket for dipstick guide tube (4).
  4. Unplug connectors (1) for turbocharger air recirculation valve N249 and secondary air inlet valve N112 on underside of retainer for electrical change-over valves.
  5. Detach vacuum hose going to electrical change-over valves at intake manifold.
  6. Disconnect both hoses from secondary air pump.
  7. Disconnect hoses from turbocharger air recirculation valve N249(item 7); re-attach electrical connector. [Note: The illustration shows the retainer for electrical change-over valves from below and removed from the engine.Illustration shows version for vehicles with secondary air system.On vehicles without secondary air system, only the turbocharger air recirculation valve N249 is fitted to the retainer for electrical change-over valves.Disregard (items 1 ... 6).]
  8. Connect test hose to the hose connection on the turbocharger air recirculation valve N249 marked with an (arrow).
  9. Switch on ignition and select vehicle system "“01 - Engine electronics”".
  10. From the menu (1) select the diagnostic function "“03 - Final control diagnosis”".
  11. Press the → key repeatedly until the following display appears:
  12. Press the ← key to exit from function "“03 - Final control diagnosis”".
  13. Press function "“06 - end output”" and switch off the ignition.
  14. Renew air recirculation valve for turbocharger N249.
  15. Unplug electrical connector at turbocharger air recirculation valve N249(item 7). [Note: The illustration shows the retainer for electrical change-over valves from below and removed from the engine.Illustration shows version for vehicles with secondary air system.On vehicles without secondary air system, only the turbocharger air recirculation valve N249 is fitted to the retainer for electrical change-over valves.Disregard (items 1 ... 6).]
  16. Connect hand-held multimeterV.A.G 1526 C to measure resistance between contacts on turbocharger air recirculation valve N249.
  17. Renew air recirculation valve for turbocharger N249. [Note: Turbocharger air recirculation valve N249 is supplied with power via fuel pump relay J17.]
  18. Connect voltage testerV.A.G 1527 B between contact (1) of connector for turbocharger air recirculation valve N249 and earth "“–”".
  19. Operate the starter briefly.
  20. Check for open circuit in wiring from contact (1) of connector for turbocharger air recirculation valve N249 via fuse to fuel pump relay J17.
  21. Repair wiring connection if necessary.
  22. Connect voltage testerV.A.G 1527 B between contact (1) and (2) of connector for turbocharger air recirculation valve N249.
  23. Switch on ignition and select vehicle system "“01 - Engine electronics”".
  24. Repeat function "“03 - Final control diagnosis”".
  25. Press the → key repeatedly until the following display appears:
  26. Press the ← key to exit from function "“03 - Final control diagnosis”".
  27. Press function "“06 - End output”".
  28. Switch off ignition and detach diagnostic connector.
  29. Connect adapter cableV.A.G 1598/31 (test box) to connectors of wiring harness; do not connect engine control unit. Connect earth clip of test box to earth (arrow)24.
  30. ⚠ To prevent damage to electronic components, select appropriate measuring range before connecting measuring leads and observe test requirements. — Check for open circuit and short to positive or earth in the following wiring:
  31. Repair wiring connection if necessary. [Note: Secure all hose connections with the correct type of hose clips (same as original equipment) Parts catalogue.]

Who makes these pages, and how

TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.

The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.

Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.

Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com

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Workshop data on this page last updated 20 Sep 2026.