Blower working but no air through vents - intermittent

[bluemoon39]

Hello

All works fine but then after about 1/2hr nearly all the air stops blowing through the vents. This is the case with A/c or Heater.
I can turn the fan up to full and hear it spinning like mad but still hardly any air through the vents. The vents still feel hot/cold but no air is being blown through.
If I leave the car for a while (maybe an hour) and it all works fine again.

I need to get it sorted because I froze my *** off last winter

Any ideas?


Audi A4 Avant 2005 2.0 TDI S-line

 

[Staz]

Most likely is the actuators that control the flaps to direct the air. Can you feel air flow anywhere? i.e. in the footwell or on the windscreen? And what happens when you select a different output?

 

[bluemoon39]

Once it stops, even if I change the air flow direction it still doesn't come out of any vents.
It's booked into garage in a couple of weeks for other work so they will be able to hook up to Vag-Com and hopefully find out what the issue is.
I'll post back any findings.