Mazda Millenia 1995 - 2.3L

When I start accelerating - like after a stop light - I have to push the pedal to the floor and the car feels like I took off in 3rd or 4th gear, although this is an automatic transmission. I was told that something is wrong with the transmission computer but so far I have not been able to locate it to test with another one. If there is someone out there that could let me know where the computer is I will be very grateful! Thanks!