Blue smoke means oil burning so turbo, headgasket or valve seals...
White means water so head gasket, head itself...
So I would say head gasket failure when your engine warm the failure increase and then it admit more water or oil so start to stall...
Do you have oil in your header tank? mayo in your oil?
Water or oil consumsion?

Changing the head gasket is'nt a full rebuilt so you may have consider it.
wait for other comments anyway...