Teekster

Any thoughts on this? 91 944 S2 cab. Whenever I deselect the AC, I get an awful noise coming from behind the dash. It goes away when AC is selected.

bonus12

That sounds exactly like a relay clicking.

I haven't verified it myself, but I found this...
The Air Conditioner Relay is a 6 post relay and is located behind the glove box to the far right. There is a small relay panel there that holds this relay and the Fresh Air Interlock Relay. The glove box has to be removed to access.

Teekster

That’s what I thought. I also read about this relay panel, but I can’t seem to find it. That’s why I took the glove box out in the first place.

bonus12

I recommend removing the hvac unit to clean all of the large contacts on the back. Examine the solder points. There are 2 solenoid relays back there I think. One controls the flapper to mix the air, which might get activated when you turn off the a/c. It never hurts to clean your grounds of you haven't.


http://www.autoatlanta.com/porsche-p...section=813-00