My malfunction light went on. I went to auto zone and they said my speed sensor was bad. anybody know the impact of this- kind of broke right now and want to know if I can drive without this for awhile
thanks

The ECM uses the speed sensor to tell it when to send instructions to various systems. For example, if you have anti-lock brakes, the ECM does a diagnostic function at 5 mph after start-up to make sure everything is working correctly.

If your interested in some background, see:
http://www.autoshop101.com/forms/h36.pdf

In answer to your question, it is an important sensor and you should get it fixed as soon as you can. It won't hurt anything for it to be inopperative, but some functions of your car may not work and you may not know about it. Brakes in particular. Get it fixed.