I just called Cummins and spoke to one of the technicians. He told me that the engine has a built in timer that will not allow it to fast idle or do anything harmful immediately upon startup without the oil pressure and system checks being cleared out by the ECM. This feature is called engine warmup protection.
He said I can go ahead and hit the fast idle speed immediately upon startup and the engine will fast idle when the engine is ready and in a position to high idle. So here's one where the computer keeps us from harming the engine.
