Just wondering if any of the Nissan guys on ExPo have had this problem. My 2012 Frontier SV 4x4 blows cold air when the RPMs drop to idle even with the engine at temp. Normally would think low fluid level first, but sitting level everything looks fine. But I've found a thread over on Club Frontier that talks about the system gathering air bubbles in the core and adding coolant to the top of the overflow tank will help purge the air from the system. Is this something any of you have dealt with? I can take it in to the shop but if the fix is that simple I would rather try at home.