key wont turn
Try moving the steeing wheel while trying to turn the key. If that doesnt work the part the key goes is needs to be taken out and rebuilt or replaced
Chevy and other gm makes have what is called a sidebar in the ignition cylinder. Over time it gets locked in place. This is the only explanation for the correct key spontaneously not working anymore. It can be forced to turn with vice grip after the plastic is peeled away to get a grip. The key must also be inserted to align the wafers, then you can force it with the vice grip. Once turned you can remove it (get instruction on YouTube) and then refurbish the sidebar (shave it down smaller) with a dremmel tool or hand-file. The refurbished cylinder can now last you another 180,000 miles haha good luck.
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