As the weather is becoming hot here in Texas, I have noticed something about my 2008 XKR that I don't remember from previous seasons. When I start the car with the AC in the "Auto" mode, it seems to take a while for the AC to begin cooling. I'm not sure is it is a time delay or if it is after I take off and the RPM's rise, but suddenly you can feel the air become cool as if the compressor just "kicked in". Has anyone else experienced this? It almost seems as if the computer goes through a boot up that takes a while to tell the AC system it should be in the cooling mode.

 

Never noticed it, but will check again.
Did you check if you got enough refrigerant?

Mine was low last year and after refilling I noticed this year that the AC compressor is whining esp. between 2k and 3k rpm after startup. The "noise" goes away after a while when the interior cooled down.
Is this normal?
Could it be the compressor or just the drivebelt?

 

I checked and cold air is starting to come after 20-30sec at 85°F outside temp.

 

It takes time to begin cooling, that is normal.