Well, the good news is, I discovered the cause of the problem. The bad news is, It's going to take a while to fix. As I was going through the the rigmarole of resetting the throttle sensor, I could hear an intermittent sound that sounded just like the faint sound of static coming from a radio speaker, The sound happened only when the key was in the on position without the engine running. The sound was coming from behind the glove box. Anybody see where this is going? Yep, there's been a mouse in the Chrysler house. After pulling the carpet back from the footwell I found a small nest. The mouse was nice enough to leave small pieces of yellow, green, and red wire-all were about three inches long. On the firewall, behind the glove box, there are two large bundles of wire running from left to right. That's where I found the matching loose ends.
My plan of attack is to take the passenger seat out and put a thick blanket on the floor. I'll probably be there for a few days checking all the wires in the bundle. Meanwhile traps have been baited and set. Battery is disconnected.
Thanks for the update. Best of luck to you!
As for the mice... "Terminate with extreme prejudice" - Apocalypse Now.