I've identified a couple of the components that the squishy and cracked hose
connects to.  It goes from the elbow between the mass airflow sensor and the
intake air distributor to the oil breather.  What does the oil breather do?
Does this piece of information eliminate this hose as a possible idle culprit?

Thanks again,
Marc Perdue, trying to get to the bottom of this mystery . . .

Marc Perdue wrote:

> Regarding hose quality, there's a kind of fat hose below the one that
> connects to the idle stabilizer valve that connects to, what, the throttle
> body, the AFM?  It's all squished and cracked.  What is this?  I know, I
> could be more specific, but I'm just getting into learning my way around the
> engine compartment of this vehicle, thanks to my crappy dealer service.
>