Why does my speedometer not work? Why does my car not shift out of first?
Possibly a VSS went bye bye, without it the speedo wont work and on a lot of vehicles the tranny won't shift, you should have a check engine light on, get the codes pulled, write then down and repost them back here and someone will help guide you through the diagnosis procedure. As you only have low gear I would suggest you borrow or rent a scanner, or like so many people do just buy the part and put it on and hope it fixes the problem.
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