Free API
4.2L V8AWDAUTOMATICgasBAT
5 active safety recalls on this vehicle — view recalls
Founding sponsor spot is openYour name on every procedure for this vehicle, permanently.Sponsor — $99 →
17965high severityPowertrain

Charge Pressure Control Positive Deviation

on 2005-2011 Audi A6 4.2L V8 · AWD

What this code means

Actual boost pressure is higher than the commanded target, indicating overboost from the turbo control system. Equivalent to OBD code P1557.

Symptoms

  • Reduced engine power / limp mode
  • Check engine light on
  • Surging or jerky acceleration

Common causes

  • Stuck or faulty wastegate
  • Faulty boost pressure sensor
  • Failed N75 boost control valve
  • Vacuum hose leak or blockage

Diagnostic steps

  1. Read boost pressure actual vs specified
  2. Test wastegate actuator operation
  3. Inspect vacuum lines and N75 valve
  4. Check boost sensor readings

Other Powertrain codes on this vehicle

🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years. Spot an error? Use the Help link above — a human reads every report.
Stuck on this repair? Take it to The Diag Desk — ask a master tech about this exact car → real human answer within 24h, never AI
⚠ STILL BEHIND THE PAYWALL
The 2005-2011 Audi A6 repair data is incomplete because no one has sponsored it yet. For $99, we generate the full step-by-step procedures, then fact-check them with a second AI pass and your expert review. Your name on every procedure, permanently.
The same data would cost $169/mo from Mitchell1 or $30/year from ALLDATAdiy — and you'd be renting access, not freeing it. Sponsor once, free forever.
Sponsor the Audi A6 — $99 →
Building an app?
Free API access to all this data — 10 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →