Engine Running

I have a 2008 Chrysler Aspen. Lately, when I turn the car off and remove the key, the engine keeps running. It takes a few minutes of turning it on and off, for it to shut off. Once the car is off, there is a heavy clicking come from the engine compartment. Any ideas to what the problem may be?

Ignition starter switch comes to mind. Not the key tumbler.

Thank you aleekat, I will try that, hopefully that will take care of it.:smile: