Now that more of this story is coming out could you fill in all of the details? This is starting to put a different slant on things and knowing the details would have possibly steered any advice off in a different direction.
So does this mean the car was at the dealer for service? If so, what kind of service?
Any engine repairs other than normal maintenance?
Any symptoms before it made a bang and quit?
And is this vehicle back at the dealer or is it somewhere else?