Okay, so I own a 2002 Lincoln Ls V6. Just recently it's started overheating while idling, but here's all the reasons it's strange. It's not my radiator because I did a flush test on it. So okay, thought maybe a blown head gasket. Nope, coolant tested clean and there's nothing in my oil. Water pump perhaps? Nope, changed that and the old one was fine. Air in the system? Here's where it gets strange. When opening the bleeder valve near the front of the engine, I can get it to bleed, but when I open the bleeder valve for the heater I get nothing. But my car blows plenty of hot air, just takes a minute to get there. Another thing that's strange is that I sat in my yard for fifteen minutes trying to recreate the overheat, switching between heat and ac. After the second or third time of switching to heat, it blew a hose off. I shut it off immediately and haven't driven it since (about two weeks ago). So I'm thinking there's a blockage somewhere, but I don't have a clue where and I need it in June for my vacation. Help!!!