One problem related to catalytic convertor has been reported for the 1999 Toyota Camry. The most recently reported issues are listed below.
Began with a ticking sound from under the car. The ticking sound was audible while the car was idling, and after the car was turned off. This problem has been going on since 2/99. I took it to dealer 3-23-99. Technician said it was normal to occasonally hear this noise while idling, because of the heat produced by the catalytic converter. Although not normal for it to continuously make the noise throughout time the car is on. Technician said he would order an entire new exhaust system for the car. The parts are in, and replacement is scheduled for March 31, 1999, at evans Toyota. I was told it was safe to drive until then.