My car is making loud blowing sounds behind the backseat, behind the back passenger's head, right under the windshield.

I turned off the heater and the radio, and it still continues to make the loud blowing sounds ... it's not a hiss, just a really strong blowing sound.

Can anyone please tell me what it could be?

The car is driving fine, but the sound makes me worry. Thanks.

 

I assume it's a Mazda 6. What year and model?
Does the sound get louder with a higher rate of speed? Does it happen at idle? Need a little info to go on.
Windshields are in the front.

 

yes, it's a mazda 6 ... year 2003 ... um, i don't know which model

no, the sound doesn't get louder with higher rate of speed

yes, it happens at idle

sorry, i didn't mean to say windshield ... i am referring to the back glass window

the sound is just a continuous blowing sound without hissing ... there isn't any wind coming out ... just the loud blowing sound ... sounds like a house furnace heater when its blowing air out ... but i don't understand why the car makes the sound even when I have the heat turned off

thanks and i appreciate any advice

 

A couple of thoughts.
One, I assume you are turning off the blower/fan, not turning the thermostat down?
Two, you had the fan relay module recall taken care of? Could be a fan noise from under the hood, but you may hear sond reflected from in the compartment? Try listening with the hood open from outside the car.
Three, disconnected vacuum hose? Same as two, listen under hood.

 

Strangely and thankfully, the car didn't make the sound when I drove home tonite ... hopefully, it was just a one-time thing ... thanks AHan !!!