93 Audi 100 CS Quattro front dash vents not blowing. Floor and defrost vents DO work. Mechanic said will $700-800 to remove dash and look for problem. Any cheaper solution?

 

Try this... Press the ECON button on the unit and see if it wakes up. My 03 A8 does this from time to time. If I press the ECON button the thing flap controller wakes up and works properly. That's a hell of lot cheaper than $700-800 to remove the dash which is almost entirely unnecessary in the 100 as the controller for the flaps and such lives just behind the glove box and is easily accessed and replaced by pulling the under dash tray and the glove box on that side. All of the flap actuators are located just to the right of the main airbox that houses the heater core.

I've had to replace the heater core and the main blower fan on my 87 5000S Q and it's nearly identical under the dash as the 100's. I can pull the complete dash in under and hour if I have to.

 

Thanks, Dave. Not mechanical so was somewhat confused. ECON button is behind glove box. Are flap actuators near heater core something different? I had the heater core (but not blower) replaced several years ago. Wish I remembered if vents stopped working around that time, but don't remember.

 

Searched again and found that cabin air filter could also affect front dash vents. Do you know where that filter would be on a 93 100 CS Quattro? Thanks.

 

The ECON button should be on the Climate Control module in the console. The cabin filter should be mounted under the hood were the air enters the climate control system. Probably under the plastic rain tray on the right side of the car under the hood just ahead of the windshield. However, if you have any air flow at all through the rest of the vents, it's probably not the filter.

 

Thanks again. I don't find an ECON button at all. Mechanic pulled the glove box. Said recirc (flap?) working. External linkages moving, but internal not moving. Found some mouse nests and other nest(s) could be a problem with flaps. Still say would need to pull dash, all-day job $700-800. Not many places work on old audis around Asheville, NC.

 

Sounds like a job for a Shop Vac. Removing the dash vent louvers and slipping a small shop vac hose down into them to see if it sucks out any debris might do the trick...

LOL Heck, if I were closer I'd help you out. I'm about 2 hours away up I26.

 

Wish you were in the area. I'll see if my handyman can remove the vent louvers, and I have a shop vac. Would be great if it were that simple, but I'm usually not that lucky. Looked at the vents and don't see screws. Read that may be attached from the back or glued in and could damage vents or dash. Any suggestions how to remove vents?