Did you take it to an auto repair shop?
That's called dieseling, and the main thing that causes it is improper ignition timing.
You need to replace the ignition switch. Too much play in it.
Does it have a remote starter? Defective ignition switch?
Defective ignition switch.
With the cylinder removed there is no easy way to turn the switch it would normally operate to the "off" position.
Turning my ignition on and wont turn off because it is faulty.
its either the starter or your ignition
Need to replace the ignition switch.
Climate control blower motor was the fix. The part cost 441 dollars.
change ignition switch and/or tumbler
It sounds like the security alarm is stuck. While this is happening take the key out of the ignition and shut the drivers door, then lock and unlock it with the key. If the problem stops even for a minute then the alarm is the problem.
bad bearing