Ignition cylinder. Mine too.
search on google or hear, you will find quite a few threads on it. Either get a locksmith to rebuild the cylinder or get a new one. There are vids on youtube how to swap them out.
There is a slight chance this is true but probably not. Try this before pulling the cylinder.
http://www.toyota-4runner.org/3rd-gen-t4rs/88044-key-stuck-diagnosis.html
You can just unplug the sensor and it will be fine just dont put it in park while you're driving.
That is a different issue. The OP says the ignition wont turn, but if he flips the key it will. that sensor will stop the key from releasing.
OP. The key is wore out. The lock only uses one side of the key. Have the dealer cut you a new key and all your problems should be gone.
That is a different issue. The OP says the ignition wont turn, but if he flips the key it will. that sensor will stop the key from releasing.