S4 Electric Power Steering Failures: Warning Signs & Help

Recently had similar issues with my 2016 Audi S5. The steering wheel symptoms you describe match what I experienced, heavy steering, inconsistent feel, and vibrations through the steering column. The root cause was a faulty power steering control module connector. The wiring harness had corroded contacts, causing intermittent connection issues with the steering system. This created erratic power steering assistance and error codes. A proper diagnosis revealed the steering pump and mechanical components were actually fine. The repair involved cleaning the connector terminals and replacing the damaged wiring section of the power steering control module harness. This is a serious safety concern that needs addressing promptly. Poor electrical connections in the steering system can lead to complete power steering failure, especially dangerous at higher speeds or during emergency maneuvers. For electric power steering issues like this, its critical to have a shop with proper diagnostic equipment and experience with Audi steering systems. The problem typically worsens over time if left unchecked. The steering system fix restored normal steering feel and eliminated all error codes. Regular maintenance since then has kept the power steering working perfectly.

Thanks for sharing that experience. I had the exact same symptoms on my S4 last year, shaky steering wheel and inconsistent power assist. The steering column was making weird noises too. My issue turned out to be both a failing steering pump and a worn pressure hose that was leaking hydraulic fluid. After fixing those components and doing a proper wheel alignment, the steering has been perfect. Did you track how much the repair ended up costing? Also curious if youve had any other steering-related problems since getting it fixed?

Just had my Audi back from the mechanic today after the power steering issues we discussed. Happy to report the electric steering system is working perfectly now. The diagnosis confirmed it was exactly what I suspected, a faulty cable connection at the control module. The repair was straightforward and cost 95 Euro for cleaning and fixing the connector. Much better than replacing the entire steering pump or other components. Since the repair, the steering wheel feels solid with no more shaking or inconsistent power assist. The electric power steering now provides smooth, consistent support at all speeds. No error codes have returned either. Your case with the failing pump and pressure hose sounds more complex than what I dealt with. Good that a proper wheel alignment sorted everything out for you. Regular steering system checks are worth it to catch these issues early. No other steering-related problems in the months since the initial repair. The control module connection issue seems to have been the only fault causing those symptoms.

Wanted to update how things turned out. Finally got my S4 checked at a different mechanic who specializes in German cars. The steering rack was actually damaged, causing the spongy feel in the steering wheel. The repair cost 850 Euro including parts and labor. They also noticed the steering column bushings were worn and replaced those while they were at it. The whole job took about 6 hours. Big difference now, no more shaking or heaviness in the steering. The wheel alignment they did afterward made sure everything tracks perfectly straight. Glad I got it sorted before any major steering system failure happened. Definitely learned my lesson about getting weird steering issues checked out quickly. The peace of mind knowing its fixed properly was worth every cent. Thanks for the helpful advice. Really helped me understand what to look for when choosing a shop for the repair.