I have a 1992 Corolla and lately I notice it puffs white smoke in the morning. The white smoke last only the first second of starting and goes away. There is no smell or leak that cause dripping (all cars leak someone somewhile.) Gas mileage is still in the mid to high 30s and everything is fine. I wonder if it is a sign to change the oil. I think the oil is due in a few hundreds miles or so but I just topped it off with fresh quart M1. This only occurs if the cars sits overnight or not driven for a few days. It doesn't occurs even if I let it sits for 5 hours while shopping.