Just bought this 2000 TJ a week ago so there is no history of why it does not work like it should. I am just getting everything working like it should. It is a 2.5 four cylinder and the heater just puts out warm air and cold air.
The temperature switch works because I can turn it to cold position and the air gets cold but when I turn it to hot position it just gets warm. There is hot water going into the heater core because the heater hose is measuring 115 degrees.
The engine temp gauge shows 1/3 way over, just a little less than half way.
What do you think the problem is?
Article source: http://www.wranglerforum.com/f210/heater-1995234.html