White smoke puffs from steering column area

I have a 93 buick lesabre ltd. With approx. 135,000miles.
while driving at average speed, puffs of smoke came from the steering column. I pulled over, checked under the hood. Nothing visible. I wated a while and started the car. Drove 1 mile or so back to work.
after work, I drove home with no further incident. Later I drove 5 miles. On my return home. It happened again. No dashboard lights came on. Also no noticable smell, although the windows were open. What would cause this and how should I proceed?
thank you