Originally Posted by
AKA Speedy
I had the same problem happen to me. Its a factory defect in the stock cylinder. Go to a GM dealership or order the new "revised" cylinder from GM parts direct. The new cylinder has a revised ramp for the spring loaded pin to move smoothly form the off, to on position. The OLD cylinder design would pit. This would cause the pin to get stuck in the pit.
It's easy to replace just when you put everything back together, make sure the pin that locks the steering wheel is pushed in. The steering wheel should be UNLOCKED at that point. If you force the cylinder back in, you WILL BREAK the dog ear off and it won't retain itself in the housing (you pull the key out and everything will come out). I just did this fix and unfortunately broke the ear off of my first cylinder, so I'm speaking from experience lol.
Here is the new part #: 92234035
Old "Obsolete" #: 92172018