2000 Plymouth Voyager Idle problem when van warms up

It would be real helpful to know which engine you have.

The 3.0L Mitsubishi engine used to have trouble with the idle air passage becoming blocked with carbon. That isn't common anymore if you use good quality gas. If this is the problem, you will not get a good "idle flare up" when you start the engine. When the engine starts, it should go up to 1500 rpm, then drop down to 800 rpm after a couple of seconds. If that doesn't occur, suspect the need to have the throttle body removed and cleaned.

Stalling will also occur if the battery was recently disconnected or run dead. Until you cause it to relearn "minimum throttle", the computer will not know when it must be in charge of idle speed. Often you will have to hold the gas pedal down 1/4" to keep the engine running.

Caradiodoc