What sensor would tell computer to load pressure to transmission?

What is your question?

When computer cleared truck runs like new. Once turned off then restarted the trans dumps hard into second gear and roughly thereafter.. mechanic says some sensor is telling computer to load pressure to trans. It is not throwing a code so how do we find out which sensor is the culprit?

What makes this problem better or worse?

Turning car off after clearing computer then turning back on

How long has your 1994 Chevrolet Blazer had this problem?

A few weeks