My '95 SLE had this problem when I bought it. It would not downshift to 1. But I could manually shift it into 1, then run it up manually through the gears. It was diagnosed by a trans shop as a broken sprag assembly. I replaced the trans with with a junkyard tranny that was more functional, but that still has TC hot lockup issues.
Even my cheapo junkyard trans came with a 6-month warranty. If it had pooped out before then, I suppose they would have given me another worn out transmission! Sometimes I wonder what it would be like to have the $$$ to do it right.