Neither of those will affect intake manifold vacuum, but the air is bypassing the MAF sensor. The port for the hose to the valve cover is in front of the throttle blades, as is the blue elbow. Not going to alter idle.

I would wonder why the PVC air supply hose on the valve cover blew out of the cover. May indicate crankcase pressure, due to excessive blowby. And the large amount of black oil in the throttle body would indicate that as well.

 

That's probably the case...not at all what I was wanting to hear

I can rub my finger on the inside of the exhaust tips and there is some moist black oil in there

Took this video last night: http://www.youtube.com/watch?v=FT_X_ZhAXKw

edit: is that oil pressure supposed to be that high?

got it scanned also:


P0430 bank 2 (passenger cat?)
P0137 bank 1 sensor 2 (rear driver O2?)
P1441 (HVAC?)

 

My 96 does something very similar. When I let off on the accelerator to shift, the rpm goes up sometimes to 1200 to 1500 for several seconds before dropping down to 1000.