My 2011 A3 Sportback (6 speed, APR flash) has 128,000 miles on it and still runs strong and problem free with one minor exception. When the engine is cold (summer or winter) there is a noticeable power loss between 3500-4000 RPMs. Once the engine reaches normal operating temperature, the problem disappears and the engine pulls smooth and strong. I'm thinking the diverter valve may be nearing the end of its useful life. Any thoughts out there from you techies? Any help greatly appreciated.

Thanks,
Chip