if it fells like the key wont turn it could be the key its self. if it feels like the key is pushing the pins out of the tumbler(you can feel it move a little). in my experience with locks you should try to avoid putting liquid lubricants into locks as they get sticky and hang up the pins in the long run. try to remove the whole tumbler and then work with it using permatex dry lube with teflon. also, i am sure you tried this, but if you turn the wheel with the key out of the ignition, the steering wheel locks up. move the wheel about a little while turning the key gently..