it sounds like heater core. usually found passenger side under dash. sometimes easy to get to other times not so easy. u should see coolant hose in n out of it. u can bypass it if its summer out but being a heater core would not be a good idea for winter. better off replacing it. hope this was helpfull
Thank you. I've asked several people this question, and they all say the heater core except for my mechanic, who wants to replace the water pump. Of course, while they are in there, they want to replace the timing belt also. I'm afraid I'm still not going to have the repair that I need done, and will have a lot of unnecessary repairs that are very costly.