12.7 burning coolant on startup sometimes???

Head gasket time. Coolant in burning in the cylinders. If your coolant is low and your low level light is not coming on, you need get that fixed also.

 

Definitely a head gasket. Why it only does it at startup, I dunno.

 

Does the exhaust smell like coolant or like raw fuel when it smokes?

 

Maybe a ‘cold leak’ until heated up.

 

That would make perfect sense except it takes more than a couple of seconds to heat up metal to expand enough to fill any little gaps.

 

IDK, but it sounds normal to me,

For the purpose of this discussion define ''low'' coolant.
The Puke tank should be MT when hot and when you release the pressure the coolant returns to the puke tank.
How does the pressure build if the head gasket is blown?
Any air bubbles in the puke tank right after high boost?
White smoke on start up is normal when the computer is in enrichment mode,