Hyundai Repair: 2003 Hundaii Tiburon Overheating problem, head gasket problems, coolant leaks

Question
I have a 2003 Tiburon. Last night my wife came home and reported the Tiburon was overheating and the air conditioning was not cooling. The air conditioner vents were blowing hot air instead of cool air. I looked under the hood to see if the serpentine belt was off, it was not and looked to be in very good condition. The car has 90,000 miles on it and we are trying to decide if this is a drive train related problem (covered by warranty) or if we should take it to a local repair shop to avoid the high dealership costs. Any help would be greatly appreciated. Thanks,

Answer
The chances of a warranty issue are small.  Check for coolant leaks.  If your water pump is leaking, it should still be covered by your warranty.  Look at the water pump and near the crank pulley for green fluid or crusty white buildup.  Other than that, your chances for warranty repair are pretty small.  I've only ever seen a handful of engine or head gasket problems leading to overheating that weren't caused by some other failure.

You'll want to get an idea where the coolant is coming out.  Check the radiator hose connections and the overflow hose from the reservoir.  If it looks like the coolant is coming out the overflow tube and nowhere else, or if you find no leaks and the coolant is full, you're probably looking at a thermostat stuck shut.

But most importantly, don't drive the car until you get the overheating fixed.  I've replaced many expensive cylinder heads because people overheated the cars so badly the cylinder head warped.