Ongoing change over valve issues on 991
#46
Race Car
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Funny! I had a fan go out as well.
But like mentioned, a near flawless 991.1 model. Just good to talk about the small details as well. Because it is a big deal if one of these COV's go out.
From the information I've gathered, it looks like this new version started somewhere in the 2016 model year. This part is currently on its fourth revision. It's also being made by a new manufacturer.
But like mentioned, a near flawless 991.1 model. Just good to talk about the small details as well. Because it is a big deal if one of these COV's go out.
From the information I've gathered, it looks like this new version started somewhere in the 2016 model year. This part is currently on its fourth revision. It's also being made by a new manufacturer.
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Now that it is warmer and I have the summer tires back on, I can't wait to go out for some more driving!
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#47
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#48
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#49
Intermediate
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I have posted this on another discussion page and thought I would try to get a response here. I have a cooling system fault on my 2014 991S (manual transmission-sport exhaust). She goes in tomorrow with them telling me they can't tell me how long they will have the car. This is the old Brumos dealership (now Fields Automotive). Actually, they found it as an "external" fault when i had her in for her 20K service 2 weeks ago--I was not seeing a fault on the instrument panel. I couldn't leave the car at that time for them to remove the bumper, etc. So she is going in tomorrow specifically for this issue which is NOW displaying full time on the instrument panel. She lit it up when I was on my way to Amelia...kept a close eye on all temps and they remained normal the entire time. Is this the problem you are all discussing? I would love to have as much info as possible before dropping her off. Thanks in advance.
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browse964 (11-11-2019)
#50
Burning Brakes
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I have posted this on another discussion page and thought I would try to get a response here. I have a cooling system fault on my 2014 991S (manual transmission-sport exhaust). She goes in tomorrow with them telling me they can't tell me how long they will have the car. This is the old Brumos dealership (now Fields Automotive). Actually, they found it as an "external" fault when i had her in for her 20K service 2 weeks ago--I was not seeing a fault on the instrument panel. I couldn't leave the car at that time for them to remove the bumper, etc. So she is going in tomorrow specifically for this issue which is NOW displaying full time on the instrument panel. She lit it up when I was on my way to Amelia...kept a close eye on all temps and they remained normal the entire time. Is this the problem you are all discussing? I would love to have as much info as possible before dropping her off. Thanks in advance.
Good Luck!
#51
Rennlist Member
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Very hard for anyone here to say for sure, but what you describe does indeed sound like a COV - caused "Coolant System Fault" yellow message. Have you noticed any difference in sound? May be the PSE valves not operating. Could be one of the vacuum hoses came off the mechanical valve. But as there are more than just a couple COVs in the 991 and all are "related" to the coolant system, it could be any one of them. There are a lot of threads here and on 6speedonline about COV's, and for kicks you could check out my blog post on same: Porsche 991 COV & Vacuum Lines Overview
Good Luck!
Good Luck!
#52
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I love it that about two weeks after something is wrong with my car the feed has posts I missed before but are being re discussed. My '14 C2S was just in for its 40K service and fortunately I live in Florida as it turns out my heat has not worked for awhile due to one of these things failing in my car. I had no idea it wasn't working and no indication of it until they checked for codes.
#53
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I have a 14 S cab. I just had this issue occur on Saturday. I do not have PSE; however, I noted a sudden increase in drone/resonance at 2000 rpm' when the engine was powering car. The very next morning, I had the coolest fault light appear. Everything else was normal. They had to remove spoiler and air intakes of get to faulty valve. Replaced it and everything is good again. Interesting how it effected the sound of the motor in the car. Wish I would have known about "F" version beforehand.
#54
Burning Brakes
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I have a 14 S cab. I just had this issue occur on Saturday. I do not have PSE; however, I noted a sudden increase in drone/resonance at 2000 rpm' when the engine was powering car. The very next morning, I had the coolest fault light appear. Everything else was normal. They had to remove spoiler and air intakes of get to faulty valve. Replaced it and everything is good again. Interesting how it effected the sound of the motor in the car. Wish I would have known about "F" version beforehand.
Side note, I think what throws people about the coolant system fault warning is that you have a bunch of different systems tied-in to the same vacuum platform in the car, and for some reason PAG decided that the only "necessary" fault message was "Coolant System." So doesn't matter if you lose heat, control of the exhaust valves, or actually have a coolant problem! Not the best human interface design if you ask me.... I remember with my '14 C4S when I first had a COV fail, I freaked-out seeing the C-S Fault warning! I was in the middle of a 2-hour drive to the shore, in 90 degree weather, cruising along at 85mph when the failure warning appeared. I didn't know whether I should pull-over and call service, keep driving, or what. Was not a happy camper at the time!
Oh well -- wondering if any .2 owners have had COV failures? I haven't researched the vacuum / COV system in the .2 cars yet....
#55
RL Community Team
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I have a question related to this on the heat operation.
I'm in Houston, so the coldest I've had my car out in has been about 45 degrees. When I first start the car, and it's cold, it's blowing cold air. Normal, but in full auto, you'd think the fan would be zero until some heat got into the system. It's not blasting, but it's still on maybe 2 or 3 bars of fan speed.
After a few minutes, it will start to blow warm air and heat as normal.
Temp set to 73 or 74 degrees.
Is this normal operation? Or maybe one of the valves is suspect?
Thanks.
I'm in Houston, so the coldest I've had my car out in has been about 45 degrees. When I first start the car, and it's cold, it's blowing cold air. Normal, but in full auto, you'd think the fan would be zero until some heat got into the system. It's not blasting, but it's still on maybe 2 or 3 bars of fan speed.
After a few minutes, it will start to blow warm air and heat as normal.
Temp set to 73 or 74 degrees.
Is this normal operation? Or maybe one of the valves is suspect?
Thanks.
#56
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Hi Plenum,
i believe it was the symposer valve. What was interesting is that they appeared to need to do a few different trial and error checks to confirm the problem valve. I'm guessing it would have been a costly repair if out of warranty.
i believe it was the symposer valve. What was interesting is that they appeared to need to do a few different trial and error checks to confirm the problem valve. I'm guessing it would have been a costly repair if out of warranty.
#57
Burning Brakes
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My understanding is that the COVs actually don't throw any error codes to the logs directly, so as you experienced diagnostics are trial-and-error approach, with likely the "usual suspects" being focus first.... You say engine noise and techs look at exhaust flap COV, Symposer -- you say lack of heat, they look at the heat exchange COV, and so on. BTW, when I lost heat on my C4S, and COV was the root cause, I never saw any fault warnings. Just no heat. Doesn't make sense to me that they wouldn't have a more specific event log..... Glad in your case it was just a COV.
#60
Three Wheelin'
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Just had all of them replaced by PNA. Had 1 go in January, another in February. Drove into Atlanta in April and had another go. Replaced by Ellis and another 100 miles later. Called PNA and they agreed to replace all of them. Took the dealer 2 full days for the work. All 4 times I got the CS fault. All replaced under warranty. By the way, I was told there are 11 on the car. PSE, MT