What is the outside temp? I have seen this when it is pretty cold ambient. The AAR actually does start to open shortly after you shut down letting in a little air when you next start. The the 12V ceramic pig in blanket heater kicks in and closes it again fairly quick. Until you shut off again - no 12V - it starts to open again. So it is the ceramic heater working - not the heat transfer from the motor.
Lets not discuss adjusting the AAR!
