Hello, I have a 1988 Nissan Sentra that I bought about 4 months ago. It has A/C and during the summer, it was great....nice and cool. Now that it's winter, it's a whole different story. The heater blows air but with no heat what-so-ever. Basically, it's the same as the fan just turned on with-out the A/C button switched on.
The strange thing is that the heater core doesn't seem to be bad. The car doesn't loose coolant. I check the coolant every other week and don't think I'ver ever had to add any anti-freeze. With the engine at operating tempature I can grip the hoses that go to and from the heater core, they are never hot. I've thought about changing the thermostat, but if the thermostat were bad wouldn't the car over-heat? If the heater core was bad, wouldn't the engine lose coolant?
Can anyone please help?