Last year I bought a 98 TJ 2.5 5 speed. Last year I had a new water pump and radiator installed. Last winter the interior would not get warm. All the heater functions work. It runs at just about 210 degrees operating temp. I checked the hoses going to the heater core today and they both are hot. Infact the outlet hose felt a tad warmer which is telling me that it's going thru the heater core okay. I have a hard top on it and it feels airtight. Infact if I place a piece of paper on the cowl vent opening and close the door, the air will blow the piece of paper off. I tried all heater positions last year and I can feel warm air coming out but it seems like the interior won't retain the heat. If I have the heater vent blowing straight out the dash vents there is hot air coming out but my legs get cold. I have a 20 mile drive to work each way and would like to stay warm. If anyone has any other idea's please let me know.