[JhwShark]

We need more details...

It turns...how by hand, when cranking by starter, will not start but turns??...
Any noise when it died??
Do you park outside?
Prior to the issue do you take short trips?
Is it very cold outside (freezing)? Could have a frozen condensate issue in your oil flow...
Have you looked at your timing belt??
Have you looked inside the coolant reservoir for oil sludge?

Do a compression check across the 6 and post results.
Jon