Hot Air
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Joined: Jun 2005
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From: Park Ridge, IL (near Chicago)
Joe seems like a good guy.
Joe also exemplifies someone who has a hard time articulating his problem. Don't get me wrong, Joe; you are not alone. I am a doctor and I see this all the time. People don't know where to start and they don't want to sound dumb. They start rambling and pretty soon they say things that aren't exactly what they want to say. I wish people would tell what they know ( how they feel) not what their theories of illness were.
Joe also exemplifies someone who has a hard time articulating his problem. Don't get me wrong, Joe; you are not alone. I am a doctor and I see this all the time. People don't know where to start and they don't want to sound dumb. They start rambling and pretty soon they say things that aren't exactly what they want to say. I wish people would tell what they know ( how they feel) not what their theories of illness were.
Thread Starter
Vegas, Baby!
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Joined: May 2009
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From: far away
I.am not trying to pull anyone's chain or be a wise guy. My Pantera is a real nightmare to work on, when you're a novice. The thing was designed by an American, built in Italy, with a Ford engine, and a German ZF transaxel. And it will never be worth anywhere near what I've got into it. But this isn't about money. Its about having a good time.
Thirty years ago I owned a 71, 911 T. Just a stocker. Expensive car for that time, ran great. The interior was lousey, screws backed out of the seats, the adjusters broke, dash split, etc, etc. I haven't wanted a Porsche since then. But the shark is different, its timeless. I really don't know squat about this car, other than its super fast. And that its a very complicated automobile.
If these cars are hot inside all the time without running the A/C, then so be it. I'll figure something out to make mine comfortable. Thnx, for your time, Joe
Thirty years ago I owned a 71, 911 T. Just a stocker. Expensive car for that time, ran great. The interior was lousey, screws backed out of the seats, the adjusters broke, dash split, etc, etc. I haven't wanted a Porsche since then. But the shark is different, its timeless. I really don't know squat about this car, other than its super fast. And that its a very complicated automobile.
If these cars are hot inside all the time without running the A/C, then so be it. I'll figure something out to make mine comfortable. Thnx, for your time, Joe
Burning Brakes
Joined: Oct 2008
Posts: 972
Likes: 0
From: Palo Alto, CA
Alan is absolutely right about the hot water valve. However, it takes about five minutes to shut off the flow of hot water to the heater core and see if that fixes the problem (or at least reduces the sauna effect). Dismantling the interior takes a lot more time and dedication, though there are some good guides out there, including this one:
https://rennlist.com/forums/928-foru...re-w-pics.html
Your heater valve may leak, but the flow of hot water to the heater core should still be restricted and you can either use that as a fix for the summer months, or you can then trace the problem back bit by bit. The first place to check is the bottom of that heater valve. See if there is vacuum getting to the actuator. Also check to see if the valve itself operates under vacuum. Alan is right in that you will probably have some mixing flap problems, but from my experience, if the heater valve isn't working properly then the car will always blow hot air. I went under my dash just the other day and found that my flaps were all properly calibrated, yet the air conditioning was not running as cold as it should have been. Some of this is due to a different problem with the system, but when I closed off the heater valve, the A/C got cooler. Maybe I have a hole in one of my flaps, maybe I've got ghosts, IDK. What I do know is that closing the heater valve can be used as a stopgap measure until you can sort out what exactly is going on, and you won't broil yourself to death while doing so. Best of luck!
https://rennlist.com/forums/928-foru...re-w-pics.html
Your heater valve may leak, but the flow of hot water to the heater core should still be restricted and you can either use that as a fix for the summer months, or you can then trace the problem back bit by bit. The first place to check is the bottom of that heater valve. See if there is vacuum getting to the actuator. Also check to see if the valve itself operates under vacuum. Alan is right in that you will probably have some mixing flap problems, but from my experience, if the heater valve isn't working properly then the car will always blow hot air. I went under my dash just the other day and found that my flaps were all properly calibrated, yet the air conditioning was not running as cold as it should have been. Some of this is due to a different problem with the system, but when I closed off the heater valve, the A/C got cooler. Maybe I have a hole in one of my flaps, maybe I've got ghosts, IDK. What I do know is that closing the heater valve can be used as a stopgap measure until you can sort out what exactly is going on, and you won't broil yourself to death while doing so. Best of luck!
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Joined: Jun 2001
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From: Ball Ground, GA
There are a couple of other things that you can check.
If the rubber seal is missing from the top of the firewall (just behind the engine on top - it holds the plastic cover on) 160 deg F engine air will enter the air intake for the HVAC.
If your vacuum system is faulty, the outside/recirculate door will always be on outside air, and you will always have air flow.
Combine uncontrolled outside air flow, hot air from the engine compartment, and/or a leaking heater valve, and you will always have hot air flow.
Using a zip tie to hold the heater valve shut may or may not shut off the flow of hot coolant. The valve may be installed backwards, so that the coolant flow pushes the blocking flap off of its seat. Or, the blocking flap may be broken. Or it may be blocked so that it can't close completely.
If the rubber seal is missing from the top of the firewall (just behind the engine on top - it holds the plastic cover on) 160 deg F engine air will enter the air intake for the HVAC.
If your vacuum system is faulty, the outside/recirculate door will always be on outside air, and you will always have air flow.
Combine uncontrolled outside air flow, hot air from the engine compartment, and/or a leaking heater valve, and you will always have hot air flow.
Using a zip tie to hold the heater valve shut may or may not shut off the flow of hot coolant. The valve may be installed backwards, so that the coolant flow pushes the blocking flap off of its seat. Or, the blocking flap may be broken. Or it may be blocked so that it can't close completely.
Burning Brakes
Joined: Oct 2008
Posts: 972
Likes: 0
From: Palo Alto, CA
Yeah Wally, I need to sort out my vacuum troubles. I just haven't had the time to tear down the console and work through the trouble areas. I know my hood seal is intact, but I'll have to check the recirculate flap.
Thread Starter
Vegas, Baby!
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Joined: May 2009
Posts: 11,555
Likes: 395
From: far away
It was and is the heater valve. Damn thing is trashed inside, stuck open. I blocked off the vacuum line, and zip tied it closed for the summer. Also rerouted the lines on the drivers side of the dash per the pictures in the tech/tip. The man lives here in Vegas, so I'am sure he knows what he's talking about.
I would like to thank everyone for your help. Car is really cool inside now, & the outside temp is over 102 today. With a black car & black interior it gets hot and stays that way, Vegas summers are nasty.
Thanks again, Joe
87 928 S4
Blk on Blk
auto
74 Pantera "L"
87 Monte Carlo SS aero coupe
84 SS El Camino
05 Tahoe, wife's ride
I would like to thank everyone for your help. Car is really cool inside now, & the outside temp is over 102 today. With a black car & black interior it gets hot and stays that way, Vegas summers are nasty.
Thanks again, Joe
87 928 S4
Blk on Blk
auto
74 Pantera "L"
87 Monte Carlo SS aero coupe
84 SS El Camino
05 Tahoe, wife's ride
