I broke my only key in my 2006 Pontiac G6 so I went to the locksmith that he cut me a new key and I programmed the key to the car the car will start but when I let off the key it dies the security sys
Sounds as if the new key is still recognizing, disconnect the battery for 10 mins and try to program it again, if that does not work you may need to take it to the dealer to reset the security system.
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