Is your B9 S4, S5 or SQ5 experiencing a ton of compressor surge? It may be your recirculation valve failing. This has been a common issue across VW, Audi and related products over the years. There are always new revisions coming out and today I'm going to replace my diverter valve with a new one. I started getting horrible surging recently and traced it down to the original diverter valve which is an older revision than the most current. My car is right around 23,000 miles at the time of the video.

Diverter Valve (06M-145-710-F) - https://bit.ly/06M145710F
Sunex 9726 Ratchet & Bit Set - https://amzn.to/3e3jNhP
Tub O Towels - https://amzn.to/3QYTuba

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