1997 Cobra. On the way home from work one day, I ran out of gas. Was between paychecks. I put cheap gas in. They next day, car had a bad knock. I immediately parked it, assuming it was something like a ring knock. But after reading quite a bit, could it just be cheap gas? I recently bought the car, it sat for years. Had to put it in shop to get it running. They flushed fuel tank, new pump, filter. Oil, filter, spark plugs. Now this... I cleaned imrc's. Drained oil, no metal. Checked under...

Knock, knock...