Removing and installing wiring harness for unit injectors — VW

🧭 Before you start

Fits: VW Touareg I (7L, 2002–2010)

Don't miss

• Only puller T10312 must be used to unplug electrical connectors on piezo unit injectors.
• Route central connector through opening in frame of mounting. Ensure it is seated correctly.
• When adapter ring is installed correctly the colour marked "shorter" stud faces 12 o'clock)

🔧 Engine codes this applies to

🔩 Torque settings

Values can differ between engine variants — check the code stamped on your block.

ℹ️ Always cross-check the exact figure against your vehicle's factory manual before final tightening — a wrong torque can damage the engine. These values are extracted from workshop data and may not cover every variant or revision.

📋 Procedure

1. Bring lock carrier into service position General body repairs, exterior50Body - front; Lock carrier - service position.
2. Remove engine cover (A) and engine compartment covers (B), (C) and (D), if fitted.
3. Remove intake manifold .
4. Remove cylinder head cover .
5. Unplug electric multiway connector for unit injectors. To do so, pull release pin (arrow 1) and loosen knurled nut (arrow 2). [Note: Only puller T10312 must be used to unplug electrical connectors on piezo unit injectors.]

6. Prise off connector from unit injector using screwdriver (arrow). To avoid canting, support opposite side of connector with light finger pressure.
7. Locate special wrench T10211 on adapter ring and loosen by turning anticlockwise through 90° (arrow).
8. ⚠ Removal and installation of the pre-wired wiring harness may only be undertaken by unscrewing the clips. Releasing the cable channel at the clips bends the clips which may break the cables due the excessive play. This also applies when changing the unit injectors and all work which does not require the central connector to be completely removed. — Unscrew securing bolts of pre-wired wiring harness.
9. Unplug connector from cylinder head and remove entire prewiring.
10. Fit prewiring and tighten securing bolts to 10 Nm. — 10 Nm (7.4 lb-ft)
11. Route central connector through opening in frame of mounting. Ensure it is seated correctly.
12. Tighten adapter ring with special wrench T10211 by turning 90° in clockwise direction.. [Note: When adapter ring is installed correctly the colour marked "shorter" stud faces 12 o'clock)]
13. Tighten central connector on cylinder head and lock in place.
14. Install cylinder head cover .
15. Install intake manifold .

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