I have a 02 f150 king ranch. When idling in park or neutral, it will shut off automatically after about 30 to 45 seconds. It is idling just fine up to that point. It shuts off just like I turned the key off. If I have the truck in drive it doesn't do it. Any ideas

 

First thing that comes to mind is if you have a remote car starter installed and it's shutting it down after a set period of time. If its not installed properly....