Two problems related to transmission not engage have been reported for the 1998 Mazda 626. The most recently reported issues are listed below.
Engine check light had been coming on intermittently. Took vehicle to dealer, who found no problem. Then, while driving about 60 mph transmission would not engage, vehicle dropped to 30 mph quickly while engine revved. Transmission needed to be replaced.
Automatic transmission had to be rebuilt at approximately 60,000 miles because gears would not engage. A private mechanic informed consumer that this was a common problem in Mazda 626.