no start, security light
Check that page out. In random coincidence, I just
responded to another post with a Security light issue, and how I managed to fix it by recalibrating the ignition sensor.
I'm not sure if it will work on a '93 LeSabre, and my '87 LeSabre doesn't have the Security system, so the actual process you have to do may differ, or perhaps not be possible at all, I don't know for sure. (Whoa, what a run-on sentence that was!) But if you CAN do it this way, it'* a dirt-cheap fix.
If it does work for you, it may only be temporary, or it might work for years. At least you can gather up the parts/cash to fix it and hopefully still be able to drive around in the meantime.