hello everyone, as can be seen from the video posted by me, there is this annoying problem that means that every time I accelerate it comes out like a sigh from the air vents (?). has anyone solved this problem? thank you in advance.

 

You have a small vacuum line that goes to the "eggs" - the white plastic vacuum tank under the center console. That stores vacuum for the vent system - to power the floor, defrost and re-circulation vents. That sound is vacuum leaking out of your tank when you open the throttle and reduce vacuum in the manifold. So either you have a vacuum leak (broken hose under hood is common) or the vacuum check valve on the intake manifold is bad. Follow the tiny vacuum line from the eggs through the firewall to about the center of the top of the engine.

I'd bet if you drove the car and turned the floor vents off - they would come on while accelerating and close when decelerating. The default for the floor vent is open with no vacuum, defrost and recirc's default is closed with no vacuum.

 

You have a vacuum leak in a line that operates the vents. You may be able to fix it by changing the one way valve that supplies the vacuum from the manifold to the vents. It's an air line, black rubber usually, with a nickel sized plastic valve. Or the problem maybe inside the dash which is harder to find, a plastic line, leaking air...

 

Thank you very much for the advice. quick what could I do? without having to disassemble the dashboard, what could i do to find this hose that has a leak? where is it placed? eventually I would have a valve to replace?

 

both those center vents are turned to OFF in the video, what happens if you open them?

 

Look for small black vacuum line connected to check valve in the very center of the engine compartment. (at the top of the manifold) follow that line to the firewall - any cracks/leaks so far? Above the passengers feet (for a lhd car) find the vacuum line and follow to the Egg carton - The face level vents are mechanical and have nothing to do with the vacuum operated vents.

 

if I open them air comes out, just as it should be but the breath continues to be emitted. slightly buried by the noise of the fan and the air coming out, but feeling always always always heard.

 

ok then you need to do what hoonk just said in post#6. if you disconnect and plug that line mentioned i believe system 'should' default to defrost.