satur9poet

Posted this here to get more opinions:

For the past week I've been dealing with a loud bang or pop coming from the driver's side a few seconds after I turn the heat on...seems to be coming from somewhere under the hood or under the floor panels. Sometimes there's also a musty smell coming from the vents but I can't find a water leak anywhere. The heater functions normally but the noise was loud and I could feel it, very strange. These symptoms are sporadic and hard to replicate.

Any ideas what the hell this might be? I'm still under factory warranty...

Mustang#5

Could be the blend door. Very common.

satur9poet

Never heard of that...what is it and is it an expensive fix? Is it causing damage to any of the heating components?

MR_Q

Mine gives a clunk when I turn my heater/ac on. Ive never noticed it to be a problem so Ive never investigated it any further than a "Hmmm. Thats odd?"

satur9poet

I see by the responses here that the noise also affects GTs. These Stangs sure are noisy sometimes--I'm totally OCD about my baby and every little clunk and noise has me sniffing around for possible problems.

Mustang#5

The blend door is the heat exchanger, it will usually run on vacuum. When you move your control from heat,defrost etc. It changes the flow of the air. The part isn't that expensive, it the labor because it's in the heater box in the dash. This is only a guess now !! I've had them go bad on Fords.

satur9poet

Gotcha. I'm still under factory warranty so maybe it will be covered.