TorqFix

Checking function — VW

Checking function on VW: 19 steps, engines AGP, AGR, AHF, ALH. What to remove, in what order, and what to check after.

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

19 steps 13 engine codes engine codes merged from 3 documented variants

🔧 Engine codes this applies to

AGPAGRAHFALHAQMASVBLFAGDAKUAMFANYASXAYZ

📐 34 workshop diagrams for AGP

Real factory drawings for this job — timing marks, bolt locations and routing. Locked in the free view.

Checking function — AGP · diagram 1
Checking function — AGP · diagram 2
Checking function — AGP · diagram 3
Checking function — AGP · diagram 4
Checking function — AGP · diagram 5
Checking function — AGP · diagram 6
Checking function — AGP · diagram 7
Checking function — AGP · diagram 8
+ 26 more diagrams
🔒 34 workshop diagrams for this job Ask about your VW AGP — free or sign up free to see the drawings

📋 Procedure

  1. Start engine and run at idling speed.
  2. Switch off ignition.
  3. Observe positioning lever on intake manifold flap (2nd person required).
  4. The intake manifold flap must, after switching off ignition, close and after approx. 3 seconds open again.
  5. Check intake manifold flap change-over mechanics for freedom of movement. To do this, operate rods by hand.
AGP? Steps differ between engine variants — check this job against your exact car before you commit to it. Check my car — free →
  1. Check function of vacuum actuator with hand vacuum pump with accessoriesV.A.G 1390/.
  2. Check that vacuum lines are connected correctly.
  3. Check variable intake manifold flap change-over valve N239.
  4. Pull connector off variable intake manifold flap change-over valve N239.
  5. Measure resistance between change-over valve contacts.
  6. Renew variable intake manifold flap change-over valve N239.
  7. Set multimeter to measure voltage and connect to contacts 1 and 2 of disconnected connector from variable intake manifold flap change-over valve N239.
  8. Start engine and run at idling speed.
  9. Switch off ignition.
  10. The voltage value must fall to 0 V after approx. 3 seconds.
  11. Connect adapter cable, 121-pinV.A.G 1598/31 to control unit wiring harness.
  12. Check wiring between adapter cable, 121-pinV.A.G 1598/31 and connector for open circuit referring to current flow diagram.
  13. Also check wiring for short to one another, short to vehicle earth and short to battery positive.
  14. Renew diesel direct injection system control unit J248.
Workshop diagrams

Ask TorqFix about your VW AGP — it answers with the exact sequence for that engine and the workshop drawing for each step. First question is free after a 20-second sign-up, no card.

Ask about your VW AGP — free → or sign up free to see the drawings

Other VW procedures

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.