Okay. My 95 avenger(i-4) was putting out heat just fine but now it only puts out a little or none. I changed the thermostat but it made no difference. I did notice that the upper radiator hose is hot to the touch but the bottom hose is barely luke warm. The overflow tank fluid is usually boiling(my temp gauge is broke so I don't know if I'm running hot or not). So is my radiator screwed or is it my heater core?

 

I would say it's most likely your heater core. Generally, when your heat stops actually heating, it's usually the core. As old as the car is, it wouldnt surprise me at all. That said, I would definitely get that temp gauge fixed.

 

yeah, temp. guage is vital. but sounds like a heater core to me

 

try to check the heater core, it might need a replacement.

 

HEAT AND THEN NO HEAT!!! The gage act`s normal. The heat starts off working great. Then after 10-15 minutes it stops and starts blowing the cold outside air in. Then sometimes it will kick back on for a little bit 5 minutes then kick back out. No set pattern on how this works or should I say doesn't work.

Also I think need a new fan belt everytime I turn the steering wheel when its cold it squeels like a pig.