Originally Posted by Finchms
It running at normal temp? At least 180°-190°. What tstat u have in it? If its not warming up to normal that will cause the heat to not be great. If its the heater core u should have some kind of leak in the passenger floor board. If the tstat is stuck ur car will try to run hot n not allow water to circulate causing heater not to work properly.
This happened to me too, I replaced my thermostat (easy) but my fan clutch is locked so it always spins... my heat still isn't great and it's cold up hear too. I really only get good operating temps cruising on the highway.