My Jeep is not getting very warm and, jeeze....it's COLD outside! LOL I replaced the thermostat today hoping that was it, but no such luck. There are no leaks anywhere that I can find. I can turn on the heater and it blows, but it's not very warm. It's not exactly cold air, just not warm like it used to be. Is there a heater core valve or something that might not be opening? Or am I looking at replacing the heater core itself? And if you have any suggestions, can you offer a simple look for or basic instructions. I'm not a moron, but I'm not much of a mechanic. 
