S8 Power Steering Failure: Vibration & Heavy Steering Alert

Had nearly identical symptoms on my 2014 Audi A7 last year. The power steering failure started gradually with steering wheel vibrations and eventually became very heavy to turn. The root cause was a failing power steering rack combined with a cracked pressure hose that was leaking hydraulic fluid. These components work together, when the pressure hose leaks, the steering rack has to work harder and can get damaged. The repair involved: Complete steering rack replacement, New pressure hose installation, Power steering fluid flush, Wheel alignment to finish This is considered a major repair that requires specialized tools and expertise. The steering rack removal alone takes several hours since the front end components need to be disassembled for access. The warning light and symptoms you describe strongly point to power steering system failure. Would recommend finding a certified shop with experience in Audi power steering repairs specifically. This is not a repair to attempt saving money on, as improper installation can lead to dangerous steering issues. My car has been steering perfectly since the repair with no vibration or heavy feel. The wheel alignment afterwards is critical for proper handling.

Thanks for sharing your A7 experience, its really helpful since Im facing similar steering column issues with my S8. The steering wheel is still giving me trouble, though not as bad as before. The fix you described with the steering rack and pressure hose replacement makes a lot of sense considering the symptoms. Quick question, do you remember roughly how much you paid for the complete repair? Also curious if youve had any other steering pump or hydraulic fluid issues since getting it fixed?

Actually turned out to be much simpler than your case. Finally got it checked by a certified mechanic who found a loose cable connection to the power steering control unit. The repair only cost 95 Euro to fix the faulty connection and the power steering has been working perfectly since then. Unlike your situation where the steering rack and pressure hose needed replacement, my issue was just an electrical fault. The steering wheel now responds smoothly with no vibration, and the hydraulic system is maintaining proper pressure. Really glad I didnt need the more extensive repairs you had. The mechanic did check the steering pump and hydraulic fluid levels while they had it, but everything else was in good condition. No issues at all since the repair was done six months ago.

I finally took my S8 to a certified Audi specialist last week after reading about your experience. The electric steering system diagnosis confirmed a failing steering rack, just as you described. The symptoms matched perfectly, the heavy steering, vibrations, and that annoying warning light. The total repair came to 2800 Euro including: New steering rack, Power steering fluid change, Fresh pressure hose, Complete wheel alignment Been driving it for a few days now and the difference is incredible. The steering wheel feels firm and precise again, no more vibrations or extra effort needed to turn. Really appreciate your detailed explanation earlier, it helped me understand what I was dealing with and made me more confident about getting it properly fixed rather than trying cheaper alternatives. The wheel alignment they did afterward really made everything come together. The car tracks straight now and handles like new.