Well, it sounds like the chip that is in your key may have broke or got stuck on a part of the ignition. I had that problem. This happened not long after I had had to have the ignition replaced?!?
how to remove crankshaft position sensor from 91 Buick Regal
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You have to remove the steering wheel, and it requires special tools.
The ignition fuses for the 1993 1993 Buick Regal 3800 is located on the car's dashboard.
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Why is my security light on and will not let my key come out of the ignition. 1999 buick regal
The camshaft position sensor on a 1992 Buick Regal looks like the end of a ratchet.
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http://www.automotivehelper.com/topic1054152.htm or Goole "ignition switch replacement 2001 regal"
I had the same problem with my 98 buick regal gs and it turned out to be the ignition switch.
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