Cavalier box problem

I have a problem with the box of my cavalier year 98, he advances speed 3, and when I decrease he does not return to speed 2, which would be my problem who can help me solve it ...

First, disconnect the plug from the transssion sensors, and the car is nodded tired and the camvios will not enter, but if you will be able to run, there are 80 and if so, the sensors are probably then, the sensors and not the transmission. But if it is pulling then it is the transmission ... when you disconnect the sensors the car lets feel normal except because it will feel tired when starting and a small suppress will vatalla ,,,

Thanks Compa. I will do the test as soon as, greetings ..

Revias ek external and internal branch, descending change control solenoid 3-2.