My car is turn on.key stuck in cylinder wont come out. have pontiac g5 09. the manual say to hold down plunger (dont know wat that is).

The lock cylinder is the culprit here, if you look closely at the key when it's in the ignition you'll see that it's crooked so when it doesn't start the lock cylinder isn't turning far enough to engage the starter. I hope this helps. Take care.

i dont know if this is electronic or cable operated there is a shift intelock which want allow it to come out of park uless the brake is depressed.mash the brake and listen you should here a click coming from the shifter if you dont pull the cover off and look and see how many cables there is if you see a small celinoid down there simply depress the plunger and see if it will come out of gear if its a cable i belive it we be on the side of the shifter unhook the cable and move the lever manually and see if the shifther will come out of park

Typically what happens is the lock cylinder falls apart and jams inside of its housing. The good news is the key needs to be in the run position in order to remove the lock cylinder. Once the steering wheel covers are removed you will see a small hole in the hosting the lock cylinder fits into. Place a small screwdriver or pick into that hole and push. This will release the locking tab that holds the lock cylinder in place. Pull out on the lock cylinder and it should pop out. A replacement can be found at your local parts store or dealer?

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The security system in the new lock cylinder has to be programed to the ecm. To do this you just have to leave the key in the run position for 10 minutes until the security light stops flashing. Hook a battery charger to it when you are doing it because if the voltage goes low during the 10 mins, you will have to start over.

In my case, out in 29 palms california, I've noticed heat expands the bolt which probably does the same to the tumblers. It would only happen in the afternoons when the steering column was in direct sunlight while I was inside working for hours. Everything would be fine, then when I left and got to home or destination, the bolt would not return home to shut off the car. I saw a suggestion in another website that said if you remove a small access door below the wheel, there is a plunger you can hold and set it back to home, but hello, the bolt and tumblers at this point have expanded from the heat to a position not resettable but a simple plunger, or resetting the cars computer for an electronic release (the initial problem is the cable down there with the plunger does not always send the signal that "I am in park." It thinks its still in Drive, so it won't let it return home.

My suggestion is to get one of those canned air for electronics, flip it upside down and freeze down the bolt, tumblers, and all metal involved in the problem here (you can see most of it once you remove the upper and lower parts of the steering column) and let the metal retract, hopefully letting you move it back to home (careful, dont snap the key). Grease the key with a small amount of motor oil to help (which you should do from time to time anyways with this vehicle).

If you are stuck and can't do that, or afford repairs at this moment, behind the wheel, below the ignition (you will be reaching back mostly behind, and there is a small plastic clip with colored wires that snap into place). Remove this when you want the car to turn "off." Removing this cable and letting it just hang there until you come back later will remove all electrical potential that is normally removed when you turn the key all the way home. It's annoying, and looks like you are hotwiring your car, but its working for me right now until I can fix it. This, is of course, assuming you are like me and the bolt is stuck fully forward, one click back from Start).

Pry off the plastic cap off the bottom of the steering column. There is a small white plunger in this access hole and press while turning the key to the lock position.

the tumblers in the ignition cylinder is jambed.
replace the lock cylinder to fix this problem

When the battery is dead, the key cannot be removed. You can either charge the battery, and remove the key or, there is a access panel (small) under the steering column, remove this, and push a small pluger to the left, while holding the plunger, remove the key.

There is a solenoid & plunger next to the ignition switch inside the steering column that stops functioning. The plunger must be retracted in order for the switch to turn all the way so the key can be removed. manually inserted the plunger and take out the key.

key cylinder pin that holds it in is stuck replace key cylinder they will give you new key along with this