Hello, I have an 1989 Ford Thunderbird and the heater isn't working properly. When i start the car to warm it up before leaving the heater blows cold air (of course), the problem is it does this everytime i come to a stop sign or sit at idle for more than a few minutes. The engine temp stays in the normal range but it blows cold air. When i take off and have went a short distance down the road it blows hot air again, but only while i'm moving. I have driven this car around for an hour and still the same thing, stop it blows cold air, take off and here comes the hot air. It's about 20 degrees outside right now and i really don't want to stand out there messing with this car until i have a good idea whats wrong with it. Any information you can give would be greatly appreciated. Thanks in advance for any help you can provide.

Thanks again,
Randall Smith

 

nobody has any idea what is wrong with my car, i find that very disturbing...lol...hope it's nothing to serious.

 

carefully feel the temperature at both heater hoses. If one is hot and the other cool or slightly warm, there is a restriction in the heater core. The temp should be the same across both hoses. You can try to flush the heater core out. Disconnect both hoses and run a garden hose through one side and see what comes out of the core. After a few minutes, flush the water through the other side. Reconnect the hoses and bleed the cooling system.