Are you holding the accelerator pedal down a little?
I have a 1993 Dodge Dynasty with 4,500 miles. I put a battery in it and drive it once every year or two. My daily driver is a 1994 Grand Voyager. I carry a spare battery because I regularly run the main one down from running an inverter to run this laptop computer. I have three other Grand Caravans that get run very little, and I have to throw a battery in them when I do. Every one of those will not stay running when put in gear unless I hold the accelerator pedal down about 1/4". This is a very common concern and you're seriously over-thinking it.
The only exception to this is if there is a bad electrical connection or a wire rubbed through and grounding out when the engine rocks. That would be very rare, but not unheard of. Usually you can make it act up by tugging on various wiring harnesses while the engine is running. A clue to this is the stalling will not occur when you shift into reverse. That makes the engine rock the other way. That would not tug on a connector, but a rubbed-through wire in a harness that is sliding on the body might still act up.
Sunday, March 12th, 2017 AT 4:53 PM