VW Touran 1.6 TDi DSG Gearbox Fix Episode 8 will it work?

Product reviewed

VW Touran 1.6 TDI with DSG dual-clutch gearbox (DQ200, dry clutch)—specifically a mechatronic + hydraulic pump/accumulator pressure issue and the DIY attempt to fix it.

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Key issues & what the reviewer did

• After reassembly, the gearbox showed flashing warnings. Faults were checked using VCDS (diagnostics laptop).
• Even after reset (and seeing no logged faults), the reviewer repeatedly observed the hydraulic pump/motor running constantly, even with ignition off / key out—suggesting pressure was not building/holding correctly.
• Using VCDS data, they checked accumulator pressure and saw it around 0.10 (transcript notes “PSI/pounds”; context suggests extremely low pressure).
• They removed/handled the mechatronic unit/pump multiple times:
  • Mechatronic and pump work done 4 times total (including disassembly/pump seal checks and reconfiguration attempts).
  • In one pass, they realized they had not purged the hydraulic oil properly after refilling.

Contamination found in the electronics area

• While working around the mechatronic electronics area, they found oil contamination in a place where there “should not be any oil”:
  • Oil/puddle in the electronics cover area
  • Oil was gel-like (“gelatin” consistency)
  • Presence of a large air bubble
• They used a USB microscope/camera (LED, ~150x zoom) to:
  • Clean oil from electrical traces/copper threads
  • Straighten contacts
  • Remove micro-contamination

Final hardware change

• They ultimately replaced the hydraulic pump with a new VW AG part:
  • The old pump was stiff to turn
  • The new pump was easy to turn
• They ensured correct:
  • Torque
  • Seal placement
  • Accumulator/housing condition (no cracking observed on accumulator housing)

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Features / behavior discussed (implied gearbox functionality)

• The mechatronic controls clutch shifting and hydraulic pressure behavior.
• Correct operation depends on:
  • Hydraulic pressure build-up (accumulator pressure should rise and then stop)
  • Proper hydraulic fluid type (special green mechatronic oil; described as non-conductive and not interchangeable with generic hydraulic oil)
  • Purging/bleeding procedure after hydraulic fluid changes
  • Electronics area cleanliness (oil/air bubbles can affect electrical conduction and pump behavior)

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Pros (what worked / positive outcome)

After the final work (pump replacement + cleaning + reset/learning):

• The gearbox reportedly became:
  • Smooth in normal driving
  • “D” driving like a “Rolls-Royce”
• No more reverse judder, which had been mentioned as a prior symptom.
• The reviewer believes the gearbox “100%” works now after corrective steps and reset/learning.

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Cons (problems / downsides)

• Symptoms could be dangerous/scary, including:
  • Jerky takeoff and clunking when engaging forward
  • Risk of stalling when pulling out from a junction
  • Grinding/crunching noise during harder acceleration (noted around 3rd ↔ 4th)
• DIY difficulty:
  • Requires proper diagnostics tools (VCDS “proper version”)
  • Requires precise mechanical steps (clutch height shimming, purge steps, correct setup)
  • High risk of expensive consequences if anything is missed or done incorrectly

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Comparisons / tool-based contrast mentioned

• VCDS “light version” vs “proper VCDS version”
  • Proper VCDS enabled more accurate configuration/testing.
  • A gearbox type mismatch was detected once (see below).
• Incorrect settings/configuration followed by “learning”
  • Manual mode driving plus a reset/learning process (“Italian tuneup” + throttle kickdown reset) allegedly helped the gearbox relearn behavior.

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Notable diagnostics / configuration details (including mistakes)

• Gearbox identification confusion:
  • One VCDS session detected “1.6 blue motion” with a DQ500 gearbox
  • The reviewer’s car is stated to have DQ200
• Test button behavior:
  • After pressing a test button, within ~5 seconds it reported “no communication with mech unit” while the unit audibly clunked
  • They backed out quickly.
• Fault codes referenced (numeric context included):
  • P17 / P176 / P177
  • Interpreted as related to:
    • gear changing speed
    • input shaft overspeed / too fast
• Reset/learning attempt:
  • Used throttle-to-floor “kickdown” procedure for ~30 seconds
  • Then key off / restart

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User experience narrative (what it felt like)

• Early stage:
  • Pump/pressure behavior wrong; constant pump sound
  • Jerky engagement and clunks
• After manual driving and learning:
  • Clunks and grinding reportedly disappeared
  • Shifting became smooth again
• Final check:
  • Engine warm-up planned so they could drain and check oil properly

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Unique points mentioned

1. Gearbox reassembled; initial restart produced flashing warnings.
2. Using laptop reset cleared faults at one stage (“no Faults found”).
3. Pump/motor noise was heard even with ignition off / key out.
4. Expected accumulator behavior: build to ~60 PSI, then pump stops (reviewer’s theory).
5. Measured accumulator pressure was extremely low (~0.10, units unclear).
6. Mechatronic unit/pump removed and worked on 4 times.
7. Pump seal/gasket orientation checked; pump plates/gear meshes inspected.
8. Decision to buy a new VW AG pump after repeated low/no-pressure results.
9. Correct hydraulic oil drain/refill performed with correct containers.
10. Purging mistake acknowledged: failing to purge hydraulic oil before.
11. Oil found in mechatronic electronics cover area where it should not be.
12. Oil was gel-like and included air bubbles.
13. Bent contacts/traces suspected due to oil/air bubble effects.
14. Cleaning done using USB microscope/camera (LED, ~150x zoom) to remove gel/oil and straighten contacts.
15. New pump characteristics: old stiff vs new easy to turn; possibly reduced motor strain.
16. No cracking found on accumulator housing.
17. Reassembly done with correct tightening/torque and bolt sequencing.
18. Gear alignment/setup steps mentioned (pistons “measure 25/25” and neutral positioning; meaning unclear).
19. Re-setup required connecting speed sensor and restoring components.
20. Symptoms later included jerky takeoff and suspected wrong clutch shimming/free play.
21. Testing required proper VCDS; VIN/car detection mismatch (DQ500 detected vs actual DQ200).
22. Test caused “no communication with mech unit” and mechanical clunking.
23. Reverse engaged smoothly after exiting test state.
24. Forward initially still lurching/clunking; later improved in manual mode.
25. “D” sometimes flashed with a spanner symbol; turning off/on cleared it.
26. Grinding/crunching during harder acceleration (3rd ↔ 4th described).
27. Manual full-gear run seemed to “cure” behavior.
28. After ~7–8 miles mostly in manual, switching to Auto stopped grinding/clunks.
29. Fault codes interpreted as gear-change speed and input shaft overspeed/fast.
30. Reset/learning via throttle kickdown helped the gearbox relearn behavior.
31. Final outcome: smooth shifting and idle around ~800 rpm.
32. Reverse judder previously present; resolved after the fix.
33. Correct oil type required because it must not conduct electricity (special green oil ~£30/liter stated).
34. Cost discussion:
    • DIY parts roughly £200–£250 out-of-pocket
    • Professional estimate up to ~£1100 if paid
    • Professional ranges mentioned: diagnosis ~£650, mechatronic replacement ~£2500+, sometimes up to ~£4500

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Overall verdict / recommendation

• Verdict: Not a typical product review, but the video strongly concludes that a correctly functioning DSG DQ200 (mechatronic + pump/accumulator system) can be restored when the pump, hydraulic purging, electronics cleanliness, and proper reset/learning are done correctly.
• Recommendation: If you have similar DQ200/mechatronic pump/pressure/persistent pump running symptoms, use proper VCDS tooling and follow purging + fluid-spec requirements carefully. DIY is possible, but the transcript emphasizes it’s easy to create expensive problems if steps are missed or if the mechatronic electronics area is contaminated.

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Different speaker / view contributions

• Single primary speaker: the DIY owner/repairer narrates observations, diagnostics, and conclusions.
• Secondary mentions:
  • Caroline provides user-experience feedback (e.g., “nearly in tears,” improved driving, reverse judder gone).
  • Friends/technicians are referenced mainly for tool support (VCDS access), not as separate technical commentators.
• No distinct contrasting technical narrator beyond the primary speaker.