Big Ape

Goes into reverse fine and it goes into low gear if you stomp on it it will shift into second but thats its could it be the VSS or is the vacume mod

jeffcoslacker

I'd bet on a modulator or the hose to it is cracked or collapsed.

richtazz

I agree with Jeff, sounds like a vacuum modulator problem. Try shifting manually, if it shifts then, it's definitely a modulator. IF it won't shift manually , you may have a valve body problem.