3 New Noises All At Once Must Be Related? Compressor?

[PorscheServiceThen529Plan]

2001 C4 Cab 58k miles. First I hear an odd ticking at idle that I would swear is coming from the driver side dash, the tick moves with RPMS and disappears at 2k rpm. Second when I turn off the engine, I occasionally hear a whine that last a second or two as/after the engine turns off- this is new too. Third tonight at idle I hear a loud rumble at idle that I thought must have been a big diesel next to me, but after a couple lights at idle I realize its coming from my car, the sound almost like that annoying rumble you get when you open only one window on the highway or a big truck engine rumble, and it will disappear if you turn off the compressor with the snowflake button, and come back when you turn it on, so it must be the compressor? Are bad things headed my way? Also it is pretty cold here in Boston now 10 degrees maybe that is making things act up? Many thanks in advance for any insight. Itching to tackle intermediate difficulty repair, if its compressor is it hard to replace?

Edited January 10, 2014 by PorscheServiceThen529Plan

[RFM]

Hard to tell but freezing temperatures can cause some additional noises inside the car, however it surprises me that the compressor makes noise when activated, the AC would not work at freezing temperatures, same system as freezers. Maybe there is something wrong with the temperature sensors?

[PorscheServiceThen529Plan]

Tonight even worse temp warmer at 29 degrees. Really shudders when you hit put it on auto and snowflake light is on. As soon as you turn off snow flake button its goes back to nice smooth running. Then when I turned the car off tonight instead of the 1-2 second windown noise after the engine stops, there was a rough shuddering wind down. Does anyone know if the compressor is supposed to still spin and wind down for 1-2 seconds after the engine has stopped or is this another sign my compressor is toast? I am wondering if a bearing has gone bad somewhere in the compressor and at idle its making the engine labor, hence, the rough rumble? and maybe the compressor is still spinning against bad friction after the engine is off?

[PorscheServiceThen529Plan]

OK I now know that it is coming from the drivers side radiator/airbox! What could it be that is triggered by the snowflake / compressor switch but is shaking the car from the driver side radiator? Any help appreciated! thanks