One problem related to transmission solenoid has been reported for the 1999 Mazda Millenia. The most recently reported issues are listed below.
While driving 40 - 50 mph, vehicle hesitated and jerked back and forth. The vehicle jerked while in stop and go traffic. Delayed shifts when accelerating to pass. There was also a grinding noise. Dealer removed and replaced defective transmission. However noise and jerking still persisted. Also the trunk release and fuel button were inoperative. The door molding needed to be replaced. Dealer wanted to replace the O2 sensor and solenoid and the door panel, trunk release and fuel button were still inoperative after being replaced. Consumer never received call back regarding parts. Vehicle was traded in.