GTI steering is either hydraulic (older) or electric (EPS) (modern) — the faults differ.
Electric (Mk5-on EPS):
- An EPS/steering warning and heavy or dead assist — usually the rack/motor unit or a fault logged on VCDS; sometimes a software update or a steering-angle-sensor calibration fixes it.
- After any alignment or battery disconnect, the steering-angle sensor may need re-calibrating with VCDS.
Hydraulic (older):
- Whine and heavy steering = low fluid or a failing pump; leaks at the rack, pump or hoses. Check fluid and for leaks first.
The fix: EPS faults often need scanning + a specialist (rack units are pricey); hydraulic faults are usually a leak or the pump.
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