2009 S6 / P2293 / Poor Acceleration

Has happened 2 times now. One day pulling out into traffic, got on the loud pedal and epc came on and went into limp mode. Cleared codes to see if I could make it come back and never did. It and didn’t happen again til today. Was in stop and go traffic for about 30 min. As soon as traffic cleared I got on it again and went into limp mode again.

What could cause this. I already replaced the fuel filter just in case. I’m wondering if I ha e a failing sensor somewhere or if it could be as bad as a failing HP fuel pump.

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