Hello everyone, just got back from a 3000 mile road trip up and down the whole east coast. About halfway through up in new england I noticed my heat was blowing luke warm/room temp air and wont get hotter then that. The weird thing was for the first time ever I had heard a very audible gurgling noise from behind the dashboard, no leaks anywhere and everything else seems to be functioning perfectly. Does anyone have any tips on this? I'm lost when it comes to heat/ac work. Thanks! (for reference its a 2002 with 235k miles)