I'm not certain how it went bad, The car was purchased this way on an Ebay auction out of FL. I can tell you that it had zero compression in cylinder #2. IIRC the seller said something about having to replace the oil pump and then this happened. I did find a receipt for an oil change at some quick lube place about ten miles ago and suspect that something happened there. We did not bother going any further into the engine since the car was purchased because the owner had a "nice" low mileage package to drop in. He had the choice of paying 10 hours to swap or many more for repair. He is keeping the "junk" one around (along with about 30 other volvo motors) just in case he can find a home for them in the future.