[s-cars] Overboost and fault codes

[Gregg Dorris]

I am a new owner of a 1993 S4 with RS2 turbo, manifold, cam, etc, done well. When boost approaches 20 lbs., the engine bucks as the ECU cuts fuel and goes into limp home mode. Fault codes are 2413 - " Mixture Adjustment, Adaptation limit exceeded, Symptom: Rich mixture, increased fuel consumption" and 2224 -  "Over boost condition Waste gate or pressure hose, Waste Gate Solenoid/hose problem" (thanks Scott - sjmautotechnik.com). I plan to check wastegate diaphragm - any other ideas?
Gregg