Sounds like the key lock pawl doesn't drop right away. Probably needs to be regreased or could need a spring replaced. I haven't heard of that problem on our Grand Prixs, but I work for a company that makes steering columns. Hope things work out for you (and doesn't cost you much either)
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"I'm on one of them there special diets. I am a precisional instrument of speed and aeromatics." - Mater