I had that happen to me on my 92. The tranny was out of an Impreza but the problem was the same. I would make sure the the throttle positioning sensor is set correctly.
It is the black thing with the brown plug.
There are three wires. Tap off the middle wire, I used a custom bend paper clip, and a Volt Ohms Meter. You should read .5 with the ignition turned on and car NOT running. It is not the adjust by loosening the two screws and rotating, little bit at a time. When you reach .5V tighten down the screws and go for a drive.
I just posted this to someone else. The TPS has a lot of conrtol over the tranny shifting. It did solve my problem. Then the tranny died a few months later.
Remember that the SVX tranny in the 92's are made of glass. they break easy.
Steve
Picture stolen from SVXFiles