heres on for ya - air blowing /sucking when accelerating

[stugc]

hi guys. have a problem with air conditioning system. have found no info online and wondering if anyone has experienced something like. when i accelerate with air con on or off the demisting vents blow or suck air(dash vents selected), (make a sound like it is). maybe ac motor regulator or something? any thoughts?

[the evil twin]

Vehicle model and engine ?

On the limited info so far a SWAG would be a turbo boost air leak if it is a Diesel... unless your cabin fan is connected to your throttle

[stugc]

hi twin, its a 09 dx 3L diesel.

[AB]

Does it happen when the setting is on the face vents and when you accelerate it changes to windscreen?

And when you decelerate it goes back to face vents?

[mudski]

I read this a dozen times and still don't get what it's actually doing.
The demisting vent blow or suck... how would they do both. Also if the air con is off and it still does the said issue, the ac pump will have no affect if it's off.

[the evil twin]

I read this a dozen times and still don't get what it's actually doing.
The demisting vent blow or suck... how would they do both. Also if the air con is off and it still does the said issue, the ac pump will have no affect if it's off.

Yeah... bit cryptic... I am guessing it is either boost leak that sounds like it is coming through the vents or a vac leak somewhere.
Agree it cannot be the A/C

[AB]

If it's as per my symptoms above the exact thing happened on Leah's vt commo and I can't remember if it was the solenoid or the vacuum actuator thingy but a very common problem on the earlier commodores.

[stugc]

yeah not sure if its sucking or blowing but when i accelerate there is air movement relative to accelerating from the vents. only demister vents available atm something has fallen into vent(can not select other options). problem arose way after this. when car is in neutral and i accelerate it doesn't seem to do it.

[stugc]

sorry dash vents = demister