Try pushing the button with the key in and turned to the left. Also work the key back and forth a couple of times. Mine was sorth of sticking in the same way and it seems a little better now. Try some lock lubricant after you get it open.

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1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T