GET "HAYNES" repair manual #38010 at your nearby auto parts store. It describes the process in detail and costs less than $20. This is too involved to describe here and you will need much patience. Forget about the "Chilton" books; they are worthless.
Possible switch or lock cylinder
if it has a lock like mine....use ur ignition key.
To change the ignition switch on a 1999 Grand Prix, first disconnect the battery to ensure safety. Remove the steering column covers and locate the ignition switch, which is typically attached to the ignition lock cylinder. Unscrew the bolts holding the switch in place, disconnect the wiring harness, and replace it with the new ignition switch. Reassemble the steering column, reconnect the battery, and test the new ignition switch to ensure proper functionality.
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Your ignition lock mechanism is worn/damaged (How much junk do you have on that key ring, Bub?). It needs to be replaced.
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Too complicated to describe here; Get a copy of Haynes repair manual #38010 at any good parts store. It has detailed instructions and some helpful pictures. Cost is about $20.
It's the ignition switch. Replace it. All will be well.
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