84 944 AC duct not opening?
07-06-2017, 12:05 AM
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84 944 AC duct not opening?
84 944 AC duct not opening?
I have occasionally checked in here but I haven’t posted in a long time.
The AC is running and I can feel an intake fan sucking in the air in the passenger foot well but there is no air at all coming out of the vents with the AC on. Is there a duct that could be closed? Does anyone know what controls that duct, if there is one? Is it a fuse or a relay? I had the AC running earlier this year when it was cold out in an effort to dehumidify the interior and after running for a while the fan fuse #6 blew. I replace that today and tried to run the AC and the problem described above reared its ugly head.
In the owner’s manual fuse #III (3) is “ Air Conditioning system” and it looks like the marking on that relay are the same as #VI – “Rear window defroster” so I was thinking of swapping them and see if that is where the problem is. They seem to have made this car with the expectation that one would never have to remove a relay. Does anyone know a trick to get a relay out that is like this small one that is nestled in-between some bigger ones? Or do I just have to pull out a whole bunch of them to clear the way to get at #3
I have a friend who is an antique car collector and every few years he has his personal mechanic recharge (or is it top off?) the R12 in this car and it has worked very well for quite a while. But this is a different problem. I actually don’t know if it is cooling, I don’t want to run the AC for too long with it having nowhere to go.
Any suggestions?
I have occasionally checked in here but I haven’t posted in a long time.
The AC is running and I can feel an intake fan sucking in the air in the passenger foot well but there is no air at all coming out of the vents with the AC on. Is there a duct that could be closed? Does anyone know what controls that duct, if there is one? Is it a fuse or a relay? I had the AC running earlier this year when it was cold out in an effort to dehumidify the interior and after running for a while the fan fuse #6 blew. I replace that today and tried to run the AC and the problem described above reared its ugly head.
In the owner’s manual fuse #III (3) is “ Air Conditioning system” and it looks like the marking on that relay are the same as #VI – “Rear window defroster” so I was thinking of swapping them and see if that is where the problem is. They seem to have made this car with the expectation that one would never have to remove a relay. Does anyone know a trick to get a relay out that is like this small one that is nestled in-between some bigger ones? Or do I just have to pull out a whole bunch of them to clear the way to get at #3
I have a friend who is an antique car collector and every few years he has his personal mechanic recharge (or is it top off?) the R12 in this car and it has worked very well for quite a while. But this is a different problem. I actually don’t know if it is cooling, I don’t want to run the AC for too long with it having nowhere to go.
Any suggestions?
07-06-2017, 12:34 AM
#2
Rainman
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hi,
there is a flap at the outlet of the evaporator housing before the air gets to the dash vents that is controlled by a vacuum servo - when you go high throttle or full throttle the AC compressor clutch disengages for max power, and the flap closes in order to keep the evaporator cold until you let off the gas a bit.
the vacuum servo is fed by a vacuum line that comes off a T on the firewall, approximately at the end of the camshaft housing behind the engine lifting hook and if i recall the vacuum line should be sort of purple or brown colored.
worst case you can remove the glovebox from the dash and zip-tie the flap open, or remove the flap completely like i did (but this requires removing the evaporator assy from the car).
there is a flap at the outlet of the evaporator housing before the air gets to the dash vents that is controlled by a vacuum servo - when you go high throttle or full throttle the AC compressor clutch disengages for max power, and the flap closes in order to keep the evaporator cold until you let off the gas a bit.
the vacuum servo is fed by a vacuum line that comes off a T on the firewall, approximately at the end of the camshaft housing behind the engine lifting hook and if i recall the vacuum line should be sort of purple or brown colored.
worst case you can remove the glovebox from the dash and zip-tie the flap open, or remove the flap completely like i did (but this requires removing the evaporator assy from the car).
07-06-2017, 01:12 AM
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hi,
there is a flap at the outlet of the evaporator housing before the air gets to the dash vents that is controlled by a vacuum servo - when you go high throttle or full throttle the AC compressor clutch disengages for max power, and the flap closes in order to keep the evaporator cold until you let off the gas a bit.
the vacuum servo is fed by a vacuum line that comes off a T on the firewall, approximately at the end of the camshaft housing behind the engine lifting hook and if i recall the vacuum line should be sort of purple or brown colored.
worst case you can remove the glovebox from the dash and zip-tie the flap open, or remove the flap completely like i did (but this requires removing the evaporator assy from the car).
there is a flap at the outlet of the evaporator housing before the air gets to the dash vents that is controlled by a vacuum servo - when you go high throttle or full throttle the AC compressor clutch disengages for max power, and the flap closes in order to keep the evaporator cold until you let off the gas a bit.
the vacuum servo is fed by a vacuum line that comes off a T on the firewall, approximately at the end of the camshaft housing behind the engine lifting hook and if i recall the vacuum line should be sort of purple or brown colored.
worst case you can remove the glovebox from the dash and zip-tie the flap open, or remove the flap completely like i did (but this requires removing the evaporator assy from the car).
07-06-2017, 01:47 AM
#4
Proprietoristicly Refined
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Check your vacuum lines behind the head on the firewall. You may have a dried out connector or a broken "blue" check valve in the lines.
J_AZ
J_AZ
07-06-2017, 07:25 PM
#5
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Inspect the actuator assembly for a disconnected/damaged vacuum line or issue with the actuator arm. It's found behind the passenger knee plate and glove box.
07-06-2017, 08:23 PM
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Pfarah7, thank you for the pictures. So far I have found a cracked hose but it is part of the charcoal canister system. I will remove the glove box cover and see what I find.
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07-06-2017, 11:19 PM
#8
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Thanks, I tend to shoot a bunch of pics whenever I'm working on something for the first time. It helps me during re-assembly and may come in handy for others. Besides, my Nikon D70 SLR needs to stretch it's legs out from time to time.
07-06-2017, 11:33 PM
#9
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BTW Maxx,
Once you remove the glove box, turn the ignition key on and, while watching the actuator, turn the AC switch; you should see the shaft move the lever. If you don't hear any noises (movement attempts by the actuator), then you may need to inspect the AC relay located to the right of the blower unit. There will be several things to check so take your time...
Once you remove the glove box, turn the ignition key on and, while watching the actuator, turn the AC switch; you should see the shaft move the lever. If you don't hear any noises (movement attempts by the actuator), then you may need to inspect the AC relay located to the right of the blower unit. There will be several things to check so take your time...
07-08-2017, 11:35 PM
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Thank you very much for everyone’s help the pictures gave me the place to look and the confidence to take it apart.
There is a solenoid valve that actuates the vacuum unit that pulls the damper door open. I bypassed the Solenoid valve and connected the vacuum line right to the vacuum unit and it opens the door. I have tested the solenoid valve and it seems to be dead. There is no resistance at all between the 2 wires on it. And I tried hooking it up to 12v to see if I could hear it make any noise and I also tried to see if when I sucked on it if applying 12v to it made any difference and it didn’t. The label on it is says 084600-3310 12v NIPPONDENSO Japan. When I try to find that part it seems to have been used in a Toyota 4x4. In the PET it lists the part as 944-573-165-00. I may just leave this bypassed and the vacuum unit connected to the vacuum line. It is blowing cool air.
Regarding the cracked hose I found. I went to the local Porsche dealer and they didn’t have it in stock. The price was reasonable but they said it had to come from Germany and would take about 4-6 weeks. I said no thank you I can get it on line a lot cheaper and I have one on the way already. I wrapped the one I have tightly with electrical tape and I reinstalled it temporarily. It may just be me but it seems like the engine is running a little bit smoother at idle.
Again thank you for everyone’s help.
There is a solenoid valve that actuates the vacuum unit that pulls the damper door open. I bypassed the Solenoid valve and connected the vacuum line right to the vacuum unit and it opens the door. I have tested the solenoid valve and it seems to be dead. There is no resistance at all between the 2 wires on it. And I tried hooking it up to 12v to see if I could hear it make any noise and I also tried to see if when I sucked on it if applying 12v to it made any difference and it didn’t. The label on it is says 084600-3310 12v NIPPONDENSO Japan. When I try to find that part it seems to have been used in a Toyota 4x4. In the PET it lists the part as 944-573-165-00. I may just leave this bypassed and the vacuum unit connected to the vacuum line. It is blowing cool air.
Regarding the cracked hose I found. I went to the local Porsche dealer and they didn’t have it in stock. The price was reasonable but they said it had to come from Germany and would take about 4-6 weeks. I said no thank you I can get it on line a lot cheaper and I have one on the way already. I wrapped the one I have tightly with electrical tape and I reinstalled it temporarily. It may just be me but it seems like the engine is running a little bit smoother at idle.
Again thank you for everyone’s help.