THIS^^^^The motor is being replaced under warranty. If there were signs of abuse, trust me, the SOA rep will call you on it (and you'll be paying for a portion of it OOP). Factory defect is sometimes a possibility, which is why a warranty exists. The resale value of your car hasn't tanked, as you are afraid it has. Keep documentation saying that it was a defect, and that it was replaced under warranty; as a buyer (and a savvy one at that), I wouldn't fault the owner, if they could prove that.