Shouldn't our AC pulley be spinning even if idle? I ask because the car tends to be a bit rough at idle AND my radiator overflow popped even though the weather and car weren't apparently hot. (didn't know until weeks later) Now I am hearing squeaking (weeks later) This makes me think the belt is not spinning as fast as it should because of the AC pulley drag, thus water pump isn't pumping as fast and POP. Also the rough idle could be the AC pulley catching now and then?