Aircon Blower Issue

[VacuBlaster]

Hi All,

I recently had a problem on my 2002 VY Berlina where the plastic pipe broke off the heater thermostat housing and my car dumped all its coolant and overheated, fortunately I stopped before it did any damage. A mechanic came out to fit a new part and all was well until the next hot day. I pushed the auto button to get the air conditioner to come on and blow air through the vents onto my face but it keeps alternating bewteen the windscreen and the face level vents regardless of what I set the blower direction. It does seem to switch to windscreen when I accellerate and then switch back to face vents when I slow down but not always, the lcd screen always shows the vent to be on face vents regardless of where the air is coming out from and the A/C unit is also okay.

Has anyone any idea what might cause such a problem?

Thanks in advance

DaVeS

[VacuBlaster]

have done a bit of investigation regarding this and it definately switches to the windscreen when accellerating, blows from both evenly if I hold the throttle constant and switches to face vents if a take my foot off. It doesn't switch quickly and I would describe it as a lazy switchover.

Does anyone know if there is a vacuum pipe involved in the blower operation because it seems that it might be vacuum pressure that is causing it. Of course I may be completely wrong.

Thanks

DaVeS

[Cosmosis]

theres a vacuum valve in the engine bay... theyre about $35 from holden... weve replaced like 5 in the past week at work. Common failing part ive been told