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Mark:Thanks for your comments and good advice. Hope you are well and also Happy New Yesr wishes.
Twilight:
I think everyone has been in your shoes as Mark said so well. We all want to see you driving your car and enjoying it. I would post a question directed at the Philadelphia 993 owners as to the top few air cooled shops. If no response PM me - I have a BMW friend there that will know or can find out. I don’t think your P dealer service route will be worthwhile. Typically they don’t have the air cooled shop guys any longer.
Mark:Thanks for your comments and good advice. Hope you are well and also Happy New Yesr wishes.
Twilight:
I think everyone has been in your shoes as Mark said so well. We all want to see you driving your car and enjoying it. I would post a question directed at the Philadelphia 993 owners as to the top few air cooled shops. If no response PM me - I have a BMW friend there that will know or can find out. I don’t think your P dealer service route will be worthwhile. Typically they don’t have the air cooled shop guys any longer.
Thanks Mike,
I am mechanically inclined. I collect, restore, and authenticate 1970 Oldsmobile 442's, oftened discovered not be 442's. I can do anything on the 442's from removing the engine, transmission, rear differential and rebuilding each. I can rebuild the carburetors, replace camshafts, set the timing, and I know every part number and can dentify any part that has been restamped. I am not boasting, but I want to be clear that I possess mechanical aptitude.
I have owned three (3) air cooled Porsche's. My first was a 1977, the second a 1985, and my current car purchased new a 1995 993 C-4 Cabriolet. All have been serviced from my Porsche Dealer.
I decided to repair my '95 to minimize my daily stress and I enjoy repairing cars. I had written about cold air at high speeds. I removed the fresh air servo motor, installed tape over the cowl duct, and experienced a noticible positive difference. I thanked everyone, and I was always polite and respectful.
My fresh air servo motor is already out of the car. I wanted to write my experience with the temperature and velocity difference, specifically on the driver's side, after my test drive.
I have no problem buying an Enthusiast device from Durametric. They too have been helpful.
I know that there are five (5) servo motors in my car. Tore's photograph was very helpful in identifying three (3) of the five (5) servo motors. I feel some of the confusion is caused by the lack of consistency in identifying part names. For example, a plastic part was referred to as a plastic clip, plastic retainer clip, and a plastic bushing that holds the servo arm to the rod. The actual name is a linkage clip and has a specific part number. The lack of of consistency causes confusion and follow up questions.
When I wrote about the temperature and velocity difference on the driver's side, the part was identified as a driver side kick panel mixing valve, driver's side footwell valve, (stuck partially open), the footwell valve, and mixing flap. The lack of consistency caused confusion. I wasn't sure if this part is the part identified in Tore's photograph #3, FootWell Servo, or was one of the motors inside the driver's compartment. And, where is the flap located.
I can buy the Durametric device. However the need for clear consistent part identification will continue to cause more questions, specifically the location without consistency.
Please fellow members, my response is meant to be constructive.
I prefer to repair this issue myself, especially since my fresh air servo motor is already out of the car. However, I do not want to frustrate any members, or myself.
I appreciate your idea to post a reputable Porsche independent in the Philadelphia area.
My Porsche dealer has the same air cooled mechanic for thirty--five (35) years.
I would prefer to repair my car for self satisfaction. This is not an issue of cost. However, as I had written earlier, I don't want to frustrate anyone, including myself.
I too want to be on the road.
Thank you for responding to Mark's suggestion.
Wishing everyone a Happy, Prosperous and Healty 2019.
Thanks again and with my appreciation.
And this may be causing the temperature and velocity difference on all of the driver's side vents, including the defroster; compared to all of the other vents including both center vents?
And this footwell valve is located on the driver's side, inside the cabin?
Anything written how to repair? Photographs?
Originally Posted by Twilightblue28A
Thanks Mike,
I am mechanically inclined. I collect, restore, and authenticate 1970 Oldsmobile 442's, oftened discovered not be 442's. I can do anything on the 442's from removing the engine, transmission, rear differential and rebuilding each. I can rebuild the carburetors, replace camshafts, set the timing, and I know every part number and can dentify any part that has been restamped. I am not boasting, but I want to be clear that I possess mechanical aptitude.
I have owned three (3) air cooled Porsche's. My first was a 1977, the second a 1985, and my current car purchased new a 1995 993 C-4 Cabriolet. All have been serviced from my Porsche Dealer.
I decided to repair my '95 to minimize my daily stress and I enjoy repairing cars. I had written about cold air at high speeds. I removed the fresh air servo motor, installed tape over the cowl duct, and experienced a noticible positive difference. I thanked everyone, and I was always polite and respectful.
My fresh air servo motor is already out of the car. I wanted to write my experience with the temperature and velocity difference, specifically on the driver's side, after my test drive.
I have no problem buying an Enthusiast device from Durametric. They too have been helpful.
I know that there are five (5) servo motors in my car. Tore's photograph was very helpful in identifying three (3) of the five (5) servo motors. I feel some of the confusion is caused by the lack of consistency in identifying part names. For example, a plastic part was referred to as a plastic clip, plastic retainer clip, and a plastic bushing that holds the servo arm to the rod. The actual name is a linkage clip and has a specific part number. The lack of of consistency causes confusion and follow up questions.
When I wrote about the temperature and velocity difference on the driver's side, the part was identified as a driver side kick panel mixing valve, driver's side footwell valve, (stuck partially open), the footwell valve, and mixing flap. The lack of consistency caused confusion. I wasn't sure if this part is the part identified in Tore's photograph #3, FootWell Servo, or was one of the motors inside the driver's compartment. And, where is the flap located.
I can buy the Durametric device. However the need for clear consistent part identification will continue to cause more questions, specifically the location without consistency.
Please fellow members, my response is meant to be constructive.
I prefer to repair this issue myself, especially since my fresh air servo motor is already out of the car. However, I do not want to frustrate any members, or myself.
I appreciate your idea to post a reputable Porsche independent in the Philadelphia area.
My Porsche dealer has the same air cooled mechanic for thirty--five (35) years.
I would prefer to repair my car for self satisfaction. This is not an issue of cost. However, as I had written earlier, I don't want to frustrate anyone, including myself.
I too want to be on the road.
Thank you for responding to Mark's suggestion.
Wishing everyone a Happy, Prosperous and Healty 2019.
Thanks again and with my appreciation.
[QUOTE=Twilightblue28A;15525578]Heyy Mike,
I was only kidding about putting black Electrical tape over the silver duct tape to match the colors...i'm going to hold off on my Indonesian tires until I fix my heating.
Also, thanks for the information on the mixing servo.
Have a Happy, Prosperous and Healthy 2019..
I know that the footwell servo is located? Acording to Tore's photographs, the footwell servo motor is located in the frunk next to the fresh air servo motor.
Where is the the mixing servo located?
Where is the driver's side kick panel mixing valve located?
Where is the driver's side footwel valve located?
Are these these devices the same?
This will help clarify my confusion.
Thank you.
Last edited by Twilightblue28A; 01-01-2019 at 10:22 AM.
Thank you! I knew from Tore's photograph that there were three (3) Servo motors in the frunk and Tore's photograph identifies the location and names of each. With your link, I now know where the additional two (2) Servo motors are located (inside the car) and what they are called. Your post is very helpful.
I already have the fresh air Servo motor out of my car.
I appreciate your link.
Thank you and Happy New Year.
Torre' Photograph
I removed the fresh air servo item #2 referred to in Torr'e's photograph. I taped the cowl vents and I receive hot air at idle and at high speeds.
Both center vents, and all three (3) vents on the passenger side are delivering hotter air compared to the three (3) vents on the driver's side ie; defroster, dash and the vent that provides heat to the floor.
Which servo motor most likely is causing the temperature difference. Servo motor #3 identified as the footwell servo motor in Tore's photograph or a servo motor inside the cabin, driver's side, not identified in Torre's photograph?
Please refer to Torre's photograph so we use the same description.
(#2 and #3 are in the frunk as shown in Torre's photograph)
The servo motor inside the cabin is not shown in Torre's photograph.
Thank you.
As I explained before it’s the mixing valve motor in the drivers side footwell by your left calf. There’s a carpeted piece to remove for access. The mixing valve is inoperative and needs to be replaced.
It is not allowing enough hot heat exchanger air past to mix w cabin or unheated outside air.
As I explained before it’s the mixing valve motor in the drivers side footwell by your left calf. There’s a carpeted piece to remove for access. The mixing valve is inoperative and needs to be replaced.
Thanks Mike,
I won't remove #3 the footwell servo located in the frunk in Torre's photograph. I will remove the servo motor inside the cabin, driver's side, behind the carpet near the frunk release.
I won't remove #3 the footwell servo located in the frunk in Torre's photograph. I will remove the servo motor inside the cabin, driver's side, behind the carpet near the frunk release.
Sounds like a plan. The one behind the carpet cover in the footwell is easy to get to other than you will be down on your hands and knees to remove it.
Andy
As I explained before it’s the mixing valve motor in the drivers side footwell by your left calf. There’s a carpeted piece to remove for access. The mixing valve is inoperative and needs to be replaced.
It is not allowing enough hot heat exchanger air past to mix w cabin or unheated outside air.
Simple to replace and common problem.[/QUOTE
Mike,
I already removed the fresh air servo. I am also removing the driver's and passenger's side servo's and sending the group to Partisan. I have been that both interior servo's often fail together.
Any suggestions where the interior servo's are located and what must be removed to access the servo's will be greatly appreciated. I have attached photographs of the driver's side, interior carpeting and frunk release. Driver's side carpeted area by my feet. Driver's side carpeted area. Driver's side carpeted area. Do I remove the screws from the release to provide carpeted cover to be removed?
Driver's side by frunk release Driver's side frunk release.
Please remember this started with my car not getting hot air at high speeds. I removed the fresh air servo motor. I taped the cowl vents and the car delivered heat at high speeds. While test driving, I noticed that the heated air was not as hot as the two center vents and all of the vents on the passenger side.
I have been given advice to replace the servo motor on the driver's side, inside my car. Ii was told that it is common for both interior servo motors to fail at the same time. I figured I might as well take out the servo motor on the passenger's side, inside my car, and send the three (3) servo's to Partisan in Germany for rebuilding. Hopefully, rebuilding the three (3) servo's will correct both issues. Whatdoyouthink?
Please remember this started with my car not getting hot air at high speeds. I removed the fresh air servo motor. I taped the cowl vents and the car delivered heat at high speeds. While test driving, I noticed that the heated air was not as hot as the two center vents and all of the vents on the passenger side.
I have been given advice to replace the servo motor on the driver's side, inside my car. Ii was told that it is common for both interior servo motors to fail at the same time. I figured I might as well take out the servo motor on the passenger's side, inside my car, and send the three (3) servo's to Partisan in Germany for rebuilding. Hopefully, rebuilding the three (3) servo's will correct both issues. Whatdoyouthink?
Its common for the mixing valves to fail and be partially open or closed and for it to go unnoticed. You’d get hot air if requested on one side and maybe lukewarm on the other side. Not something you’d notice right away if at all.
The trunk servos are unrelated to the mixing valves right and left.
Long time since my drivers side was replaced but I think the pictured screws and plastic piece comes out and there are other screws hidden in the carpet and near the footrest.
Not sure why you sent perfectly good and operating servos away for refurb. You have a low mileage garage queen so doubt they see much use. It seem to me the fresh air servo would be the most active unit and most prone to fail.
Its common for the mixing valves to fail and be partially open or closed and for it to go unnoticed. You’d get hot air if requested on one side and maybe lukewarm on the other side. Not something you’d notice right away if at all.
The trunk servos are unrelated to the mixing valves right and left.
Long time since my drivers side was replaced but I think the pictured screws and plastic piece comes out and there are other screws hidden in the carpet and near the footrest.
Not sure why you sent perfectly good and operating servos away for refurb. You have a low mileage garage queen so doubt they see much use. It seem to me the fresh air servo would be the most active unit and most prone to fail.
I appreciate your response as well as any other members help.
As I understand, my car has two (2) seperate issues:
1. At high speeds, I wasn't getting heat inside of the car until I slowed or idled, and under slower speeds or at idle my car delivered heat. It was suggested that the lack of hot air was due to an innoperative fresh air servo motor located in the frunk. It was further suggested that I tape the cowl vents, test drive the car to determine if I had heat at high speeds, and I do. The conclusion was to rebuild the fresh air servo motor. I have removed the fresh air servo from the car for rebuilding.
2. The second issue is what you and I are both describing: the temperature from all of the vents is less hot compared to the temperature delivered from both center vents and all three vents on the passenger side. The recommendation was to replace the servo motor inside the car, driver's side, near my thigh. I have posted photographs of the driver's side in order to identify what must be removed to access the servo motor for rebuilding.
Issue 1, no heat at high speed will be corrected by rebuilding the fresh air servo motor. Issue 2, temperature difference, will be corrected by rebuilding the servo motor located inside of my car, driver's side, near my thigh.
Please advise whether or not I'm clear with respect to the scope of work required to address both issues.
Thank you and any others help in advance.
Any problem with the HVAC servos is not diagnosed by observing the air streams or temperatures, but by testing the servos by using the control ***** on the CCU.
Our DIY pages contains a test procedure for all servos and fans, this is done in ten minutes.
Cheers,
Tore
12-30-2018, 02:27 PM
