It sounds to me like you have a fuel to combustion air intake problem caused by faulty coordination between your fuel injector system and your 'fresh air' intake to the cylinders of your Dodge Ram engine -- say *I*, who knows *nothing* about fuel-injected engines.
If we were dealing with an old carburetor fuel/air feed to the engine, I *think* I could diagnose your problem very quickly. I would say that when your engine was cold, the automatic choke device on your carburetor was working properly to set your engine to start up with an air-starved fuel mixture and a 'high-idle' throttle setting. And then, when the engine warmed up to proper running temp., the 'high-idleing' device would 'drop off ' to normal engine idle rpms. If, at that point, the engine did NOT drop down to normal idle rpms, but *DIED*! -- I would say that the 'warmed-up' engine carburetor and throttle settings would have to be adjusted to *keep* the engine running at the proper idling rpms.
Now, if you can just find someone to translate *this* info. concerning carburetor fuel-controlled engines to apply in some way similar to the control operation utilized in fuel injection engines -- uh, well -- good luck!
