2000 Ford Mustang Conv. Heater issue
 

I have strange problem (or is it normal) with the heater on my Mustang. It blows cool air when turned on to blow hot air. When I turn it off and wait a minute or so and turn it back on it blows hot air for like 10sec then cool again.

Also it seems to blow hot air when I drive at least 30mph - when I am stuck in traffic I just get cold air from the heater.

What could be the problem?

Re: 2000 Ford Mustang Conv. Heater issue
 

More info: its a V6. Heater works when accelerating, after few seconds it blows hot air, then when one stops air starts to cool down.

Re: 2000 Ford Mustang Conv. Heater issue
 

well could be a few things ..over cooling like: t-stat stuck open, bad temp sensor keepin the electric fan on or faulty clutch fan..low coolant...i would prolly change the t-stat first its only like 8 bucks