1997 Firebird heater problems

My 1997 firebird heater will not get hot. I've replaced the thermostat and replaced a couple of hoses, but still no heat. Any help or suggestions would be greatly appreciated. Thanks, Michelle

Is the hose going to the core hot?How is the heat controlled in your car with a blender door or water valve,might want to check them.Do you have an air pocket in the core? Have you back flushed the core? Also might want to go to Firebird board to check for problems specific to your model.Good luck
Unbe