steam

On first start up of any car in the morning fuel is not being atomized properly and doesn't burn properly until the engine reaches proper operating temperature. An engine that is burning oil emits blue colored smoke that has an odor of burning oil. It is heavy blue to blue gray in color. If the engine has worn valve guides or valve guide seals oil may drip into the cylinders when the engine is turned off and allowed to cool, then when you start the engine up in the morning you get that trail of smoke out the exhaust. light colored smoke out the exhaust is normal until the engine warms up, especially noticeable on cold mornings dense air. White or sweet smelling smoke out the exhaust perhaps accompanied by rough running would be a sign of a blown head gasket. You will notice grayish colored smoke out the exhaust pipe until the engine warms up. If you are loosing coolant and having to top up the coolant level frequently it may indicate signs of a blown head gasket and needs to be investigated to avoid doing serious engine damage.