Two problems related to front air bag have been reported for the 1998 Toyota Sienna. The most recently reported issues are listed below.
On oct 14th 2006 at about 4:45 pm I was driving in a parking lot at slow speed. I came to a stop and then tried to make a right turn. As I turned the wheel and applied the gas the steering column made a noise like breaking plastic and the car moved in a straight line despite the wheel beeing turned. I increased the turning motion until it was clear steering had failed. Since the lot was empty I brought the car to a stop without incident. I had the car towed to sandy springs Toyota and was told that the steering shaft had broken at the "knuckle" where the column connects to the shaft. In addition I was told that the spiral cable to the airbag had been damaged in the incident. My concerns are that had this occured at high speed or while already in a turn or in traffic the results would have been catastrophic. In addition the failure of the air bag meant that had I in fact had a collision I would not have had the protection of the airbag. I drive this car daily and I did not detect and change in steering or handling that would have been a warning. The car was repaired and has driven nromally since. I do not know what happened to any replacement parts.
While driving at 30mph vehicle was hit in rear and slammed into a vehicle in the front, and none of the air bags deployed on impact.