Hot Air from Vents when AC/Fan is OFF and Temp set to COLD?

[Matchu_Peechu]

Hi All; pretty new to the forums...

I have a 2008 MX-5 GT Soft Top purchased pre-owned 2 years ago. A while after first purchasing the car I noticed there was hot air blowing from the footwell vents even when the vent/AC was turned to off and the temp set to its coolest just in case. It happens no matter what setting the vents are at just changes where it's blowing from.

Anyone else have this problem in their Miata? Not sure what I can do short of taking it to the dealership or diagnosis?

Thanks for your thoughts and ideas!

Matchu_Peechu

Happy Topless Travels to All!

 

[THE Phen]

I get a lot of heat from my car, but it's from the exhaust. That silly turbo gets quite warm at times...

 

[WillD]

My Miata blows warm/hot air through the vents unless my AC is on all the time but then it's a 1991. But it wouldn't hurt at all to take the car to the dealership to have it checked out.

 

[big Lou]

The Heater core valve is probably stuck open or has even melted. Did you check the cables and make sure it's still opening/closing the valve?

 

[bazooka joe]

aren't you just pulling in outside air at this point?

 

[chiefmg]

I don't know about NCs, but the earlier models are known to sometimes have issues with the mixing door on the heater unit getting out of adjustment and causing the problem you describe. As mentioned a couple of posts up I'd first check to make sure your controls are moving what they are supposed to, then see if the door is being positioned correctly.