I have a 2001 Silverado, 5.3l, two wheel drive. The truck was driven about twelve miles and ran fine. Engine was shut down, no problems. Later the truck was restarted and moved to a new location a short distance from where it had been parked. When the ignition was turned off the engine continued to run and the truck shook violently. Turning the ignition back to the on position the engine restarted and ran. The attempt to turn the ignition off a second time had the same results. While the truck is shaking all of the warning lights are also flashing. Once again the ignition was turned back to the run position and the engine restarted and seem to run a little rough. The third attempt to shut it down went smoothly. After the engine cooled down my wife tried to restart the engine. As soon as she opened the left door the chime started sounding as if the ignition key was in the ignition. There was no key in the ignition at this time. The truck did start and shut down at this time. This morning she tried to start the engine and turning the key had no reaction at all. No lights, nothing. Any suggestions would be greatly appreciated. I can check for codes when I get back in a few days. Thank you for any help in advance.