exhaust smoke upon start - up on 2002 Nissan Pathfinder

Upon start-up about 50% of the time a large amount of white smoke comes out of the exhaust.
After driving about 1/2 - 3/4 of a mile the smoke is is gone.
I've noticed it usually happens when the engine is cold.

Had it tested twice, and unfortunately it did not smoke when tested. Any ideas?

Asked by for the 2002 Nissan Pathfinder
Pull your plugs and look for oil or water. If it's oil it could be leaking in from the valve guides, water a head gasket or crack in the head or block.
1 more answer
Sounds like a head gasket. As the vehicle warms up the leak is sealed by the expanding engine parts.