intake manifold gasket (GM3800) gone bad then good?

[Kyle Einarsson]

L26 engine, low mileage, but 15 years old:
When starting in the morning, misfires and spews out white smoke.
Pulling off spark plug leads, it appears that the cylinders 5 and 6 are
the guilty ones. But once the temperature guage reaches 1/4, the smoke
stops and it runs smoothly. So the white smoke usually means coolant
from a buggered gasket. Intake manifold gaskets are a common failure on
old GM3800 engines. But why only part-time problem? Is it possible that
when the engine is hot, the gap in the gasket is closed?

[Scott Dorsey]

Could be. Or maybe the block or manifold is cracked. You'll know once
you have it apart.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."