id say you have a problem with little knowledge on this id say it could be a couple of things. 1.thermostat maybe bad. 2. id say blocked heater core. 3. dirty coolant system. start off first by running some coolant system cleaner and flush the entire thing even the heater core lines.
Never tell people how to do things. Tell them what to do and they will surprise you with their ingenuity."
General Geroge S Patton
automatic trans, 4.10s with L/S
ported and polished TB
4brand new speakers with inslation in doors
smoked tail lights
20%tint on driver and passenger windows
5% tint on back window