I have a 1992 Dodge Dakota v-6 it runs and takes.

What does "takes gas well" mean?

I get the impression the engine stays running as long as you hold the gas pedal down. If that is correct, it sounds like the battery might have been disconnected or run dead recently. If so, the Engine Computer lost its memory and has to relearn "minimum throttle" before it will know when it must be in control of idle speed. It also might not give you the normal "idle flare-up" to 1500 rpm when you start the engine. To meet the conditions for the relearn to take place, drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the brake or gas pedals.

The next most likely cause would be a wire rubbed through and grounding out when the engine shifts when it's put in gear. To find that you would need a scanner that displays live data to see what the Engine Computer is seeing. In particular you want to look at the "AIS steps". That's the step number, from "0" to "256" the computer has placed the automatic idle speed motor to. If it's on "0", the computer has not relearned minimum throttle yet. "32" is about typical for a good-running engine. With one cylinder misfiring, you'll find it at around step "50".

You can also look at the crankshaft position sensor and camshaft position sensor to see if either signal is lost when you shift into gear. Missing either one will cause the engine to stall.

For clues, if a wire is rubbed through and grounding out, the engine should not stall when shifting into reverse because that will make it rock the other way. If it still stalls, it is still idle speed-related.