968 Climate control issue
#1
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I'm looking at purchasing a car, it has one known issue...
The climate control will occasionally cycle from cold to hot and then back again... It sounds like the heater valve is cycling. My understanding that it is likely that it's a controller in the dash causing the problem. The question is... what is the most likely scenario? How big of an issue? What kind of bucks are we talking?
thanks
John S.
The climate control will occasionally cycle from cold to hot and then back again... It sounds like the heater valve is cycling. My understanding that it is likely that it's a controller in the dash causing the problem. The question is... what is the most likely scenario? How big of an issue? What kind of bucks are we talking?
thanks
John S.
#2
Team Owner
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no.
fill the overflow reservior and just drive normally for a while.
problem will go away almost immediately.
but, it may require two fills before you're 100 % full.
fill the overflow reservior and just drive normally for a while.
problem will go away almost immediately.
but, it may require two fills before you're 100 % full.
#3
Nordschleife Master
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It's likely the vacuum switch on the right side of the torque tube tunnel.
#4
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If the CC head is bad, you can replace it with a used one but there are a few different versions. Later IMO is better. The earliest ones are bigger and heavier and use less integrated circuitry. The 968 head uses a detent pot on the temperature but that is no big deal.
I would also make sure the coolant is bled and that you have a good vacuum signal to the system before getting a new CC head and swapping it in. A loss of vacuum to the heater valve will cause it to default open. This valve is a failure point and many suggest replacing it with a stronger or newer part if it is getting old. I have also seen these valves fail and pass coolant to the heater core even when shut.
-Joel.
I would also make sure the coolant is bled and that you have a good vacuum signal to the system before getting a new CC head and swapping it in. A loss of vacuum to the heater valve will cause it to default open. This valve is a failure point and many suggest replacing it with a stronger or newer part if it is getting old. I have also seen these valves fail and pass coolant to the heater core even when shut.
-Joel.
#5
Instructor
Thread Starter
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How much are used control heads going for.... It looks like a new one is $700...
So I'm at a crossroads... The guy won't come down that much and due to the intermittent nature of the problem ( as he describes it) I bet it's the controller.
So I'm at a crossroads... The guy won't come down that much and due to the intermittent nature of the problem ( as he describes it) I bet it's the controller.