35mph-40mph not change 2-3 overdrive automatic-transaxle

it comming emission engine lamp AFTER 1 MIN .
not overdrive,after 30 min not reverse(R)(BAD REVERSE)
HAVE ER TIPS?

Do you have that diagnostic connector near the parking brake release handle? If yes, it is probably OBD1: use a small wire to connect terminal B to A (top rightest). TUrn key ON: will flash once , then twice (code 12: diagnostic is ON) then read the lights: like 3 flashes and then 4 flashes is code 34...etc, there may be mode codes. Once finished, it returns to code 12.
If you have OBD2 and will need a scanner to retreive the codes.