I have a 1993 buick lesabre. The security light is flashing and will not start. I checked the fuse it was ok. I tried our other key and still wouldn't start.

There may be a broken wire from the ignition swith going down the steering column,theres two sensors at the begining opening of switch, sometimes they get stuck and dont pop back out, in turn it doesnt touch the chip on the key and cant read it,take a look with a light use a small pic and push lightly on them and see if the y push in and pop out, if they do then replace ignition swith,theres a way to bypass,use an omh meter and measure resistance of key chip, then buy a resistor with the same value,and connenet to wires from switch under the dash,cut wires and put conecting the two going to switch with resistor connecting them together,heres a diagram,

Leave key in ingnition for about three minutes till lite goes off then start