October 24 my check engine light went off and threw code PO456. The next day I took it to get checked out and was told it wasn’t a big deal, possible gas leak or needed a new gas cap. Last week the light went off. Yesterday my car randomly started shaking and the check engine light flashed. I got my car to the auto shop within 5 minutes of that. Today they tell me my entire engine likely needs replacing. Does that sound right? Last month they said everything looked fine. Unfortunately that’s not documented.