Vacuum actuators
#1
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For some reason, it seems that I cant find vacuum actuators for HVAC system. Im searching web using PORSCHE VACUUM ACTUATOR words, but nothing comes up. Anyone can suggest where to find them?
Another question: should air blow thru central vents constantly, no matter what position of air distribution is chosen? What I got is that flow of the air from central vent is changing just a little bit when I switch air direction to, lets say, windshield.
87 S4 Auto.
Another question: should air blow thru central vents constantly, no matter what position of air distribution is chosen? What I got is that flow of the air from central vent is changing just a little bit when I switch air direction to, lets say, windshield.
87 S4 Auto.
#2
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Art, Roger at 928srus has them. The air direction should blow thought the central vents at all times, but much less when you change direction. Maybe your mix flap actuator is out, or - hopefully not - your defrost flap actuator. Best to check by putting a vacuum pump on all five vacuum lines.
#3
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Check for a floating ground on the actuator bank, I had this problem and used a 1a slow blow fuse (paranoid) to pull them to ground. Only thing now is that my heat does not work except for defrost mode, so I suspect I have one bad unit there.
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Yep all in stock and ready to fly 8>)
Recirc diaphragm is $10, Center & footwell diaphragm are $37.50 each.
Defrost is $46.95.
Roger
Recirc diaphragm is $10, Center & footwell diaphragm are $37.50 each.
Defrost is $46.95.
Roger
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
#6
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Replacing the diaphragm is the easy option. To replace the actuator you have to drill out all the rivits.
Just remove the top of the actuator and replace the diaphragm.
Plenty of tutorials to show you how. Also you save a ton of $ over the price of the complete actuator.
Just remove the top of the actuator and replace the diaphragm.
Plenty of tutorials to show you how. Also you save a ton of $ over the price of the complete actuator.
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Can I presume you have the diaphragms, too?
(Diaphragms - now there's a word you have to think about to spell as you type.)
will
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#10
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Hi Roger,
Im looking for some other parts for my 87 S4 besides the footwell diaphragm. Let me know if you have air box straps (4), heater control valve (1).
Regards,
George
Im looking for some other parts for my 87 S4 besides the footwell diaphragm. Let me know if you have air box straps (4), heater control valve (1).
Regards,
George
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Get just the diaphragms. Once you get in there, you'll see that putting diaphragms into the old cans while still mounted is so much easier than trying to R&R the whole thing. Trust me.