After replacing the LIM gasket on my 3rd gen, the hunting idle has disappeared.

It has been replaced by an idle that is way too fast.

When the coolant temp hits about 185 degrees, the idle jumps immediately to 4000 RPM. The idle speed prior to that is about 1700.

The TPS voltages as read on the PowerFC commander are just slightly out of spec, about 0.06 volt.

I will adjust them within spec, but need to know what else I should look for.

What part of the idle system would cause the idle to jump to 4k and stay there when the car gets up to temp?

This is a single turbo car, if it makes a difference.

Also, it appears a vacuum hose may be missing. I haven't yet found in the manuals just what this piece is, but I'm pretty sure there was once a hose on it.

Missing hose connection?

FWIW, I didn't do the single turbo conversion, so I'm not sure what all changes were made to go single turbo.