I have a '93 Subaru Impreza hatchback. (Sorry if this isn't the place to post this, but where's the Impreza category?) For a while, the automatic gearshift has gotten stuck in park. Oddly enough, I found that by hitting the dash right above the glove box, it would become unstuck. This technique has worked for a while, but it seems to be becoming less effective. Any idea what may cause this problem?