1994 Cadillac Deville White Smoke

Help Please! :0) I had just recently replaced the Oxygen Sensor (Cali. Emissions) 1 because some idiots burned the components and 2 because the car was smoking severly. The car ran good as new until 2 days later when it started up again. I'm sure it's the burning of fuel that I see but just don't know what is causing this to happen. Can it be the other oxygen sensor underneathe, fuel seeping through gaskets or what? Engine runs great, has new radiator & hoses, new fans and new a/c. The smoke comes on and off. Drove just fine with no problems back and forth to kids school on Tues. Then it starts again today. I was told that it could be something simple as sealing the gaskets fromthe outer portion without opening manifold which would be costly. The car has a mind of it's own and tends to accelerate when stopped. Help! :0)