Ongoing change over valve issues on 991?
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Joined: Dec 2013
Posts: 675
From: Chalfont, PA
Rep Power: 55
Anyone had had tuning flap and/or air cleaner box flap valve(s) fail. Did it result in a different sounding car?
My S has developed a droning around 2000-2500 rpm, that is rather annoying. It was intermittent at first, but is now permanent.
(It is not sound symposer related -- tested that by disconnecting tube to make sure. Stock exhaust is loud on startup, but quiets down as per usual, so think those valves are working.)
Had it in for check at dealer -- but came back with the dreaded "sounds normal to us" (it does not).
Thx guys.
My S has developed a droning around 2000-2500 rpm, that is rather annoying. It was intermittent at first, but is now permanent.
(It is not sound symposer related -- tested that by disconnecting tube to make sure. Stock exhaust is loud on startup, but quiets down as per usual, so think those valves are working.)
Had it in for check at dealer -- but came back with the dreaded "sounds normal to us" (it does not).
Thx guys.
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Joined: Feb 2012
Posts: 313
From: Mid-Atlantic
Rep Power: 33
Thx guys. Figured I'd loop back with the solution to my droning. It was (unsurprisingly) a bad change over valve -- the exhaust one.
Once it fInally arrived after a long wait for backorder, the car is back to normal.
The new part is the one ending in F.
I have a letter in to PCNA requesting replacement of my remaining 7 second generation valves, as I am sure they will eventually fail, too. I am hoping that Porsche will do the right thing and issue a second round of the campaign to switch to the new and improved valves. The new valve has a different electric connection with a shroud to keep moisture out. It requires a little wire harness adaptor.
Once it fInally arrived after a long wait for backorder, the car is back to normal.
The new part is the one ending in F.
I have a letter in to PCNA requesting replacement of my remaining 7 second generation valves, as I am sure they will eventually fail, too. I am hoping that Porsche will do the right thing and issue a second round of the campaign to switch to the new and improved valves. The new valve has a different electric connection with a shroud to keep moisture out. It requires a little wire harness adaptor.
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Joined: Nov 2014
Posts: 3
From: Long Island, New York
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Fbroen,
My service advisor was able to get Porsche to replace all my valves at once. He convinced them that the cost of labor for each failure would outweigh the cost of doing them all at once. So I've got all new valves... but still errors. Very disappointing.
My service advisor was able to get Porsche to replace all my valves at once. He convinced them that the cost of labor for each failure would outweigh the cost of doing them all at once. So I've got all new valves... but still errors. Very disappointing.
I do not mean to light a fire for nothing, but I got increasingly concerned by what seems to be a lingering issue with change over valves in the 991.
Here's a picture of the part in question (the part number is 7PP906283B, now replaced by 7PP906283C):
Based on a quick research on the internet, it looks like Porsche was aware of the issue for early 2012 builds and that launched a recall campaign (WC-43) intended at replacing 8 of these valves.
In my case, my sport exhaust stopped functioning and 3 out of the 4 change over valves I have checked were bad (I did not check the others).
There are also various threads about 991's built at different times that have had heating/cooling system issued. Again, the same part was the culprit.
I find it intriguing that it has been going on for so long and that Porsche has apparently not resolved the issue.
The first concern I have is that you may not always detect that something is wrong: it is only when my sport exhaust stopped working properly that I discovered it, but the valves controlling the symposer and the intake flap were already bad. The second concern is that I read that this part would be used in more critical components (PDK).
Change over valves (simple solenoids in fact) are a very common part and Pierburg, the manufacturer, supplies it to a lot of car makers, including for the previous 911 models. This part number is specific to the 991 and seems to be the one having an issue. They may not be sealing properly allowing moisture in, causing the valves to malfunction over time.
I am not posting this to alarm you but to keep this in mind and report if you had other issues resulting from the failure of that same part.
Having already had 3 bad solenoids, I intend to drop the car at the dealership to get it checked.
Here's a picture of the part in question (the part number is 7PP906283B, now replaced by 7PP906283C):
Based on a quick research on the internet, it looks like Porsche was aware of the issue for early 2012 builds and that launched a recall campaign (WC-43) intended at replacing 8 of these valves.
In my case, my sport exhaust stopped functioning and 3 out of the 4 change over valves I have checked were bad (I did not check the others).
There are also various threads about 991's built at different times that have had heating/cooling system issued. Again, the same part was the culprit.
I find it intriguing that it has been going on for so long and that Porsche has apparently not resolved the issue.
The first concern I have is that you may not always detect that something is wrong: it is only when my sport exhaust stopped working properly that I discovered it, but the valves controlling the symposer and the intake flap were already bad. The second concern is that I read that this part would be used in more critical components (PDK).
Change over valves (simple solenoids in fact) are a very common part and Pierburg, the manufacturer, supplies it to a lot of car makers, including for the previous 911 models. This part number is specific to the 991 and seems to be the one having an issue. They may not be sealing properly allowing moisture in, causing the valves to malfunction over time.
I am not posting this to alarm you but to keep this in mind and report if you had other issues resulting from the failure of that same part.
Having already had 3 bad solenoids, I intend to drop the car at the dealership to get it checked.
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Joined: Dec 2013
Posts: 675
From: Chalfont, PA
Rep Power: 55
You know, I find it very interesting that although the C-O-V issue seems to be an ongoing plague for 991/911 owners, there hasn't been any concentrated effort by PAG to address via campaign, recall or any other communications to acknowledge the issue with a part that is known to be faulty, allowing moisture to enter the solenoid and eventually cause failure of the part. There are many on this forum and others that have not only reported this problem (and some of us have done so numerous times because Porsche won't replace all 8 unless they all fail!) but had to return to service departments to remove failed parts and install replacements. Even the dealer SAs know this is a "common" problem! The part was revised, modified to prevent moisture, and who knows what else, and yet NADA from PAG, PCNA, or anyone else for that matter.
Now compare that to the recent global recall for a "potential" failure of some unknown facet of the hood latch mechanism, as covered in a previous thread on this and other forums: Porsche recalling 4,400 911, Boxster and Cayman models over hood latches I can't recall a single case on this or the other 3 forums I participate in where someone has reported any problem with their frunk or engine cover latches....
But then, maybe it is purely one of liability? I can understand how a hood latch failing while under speed is potentially a much more costly legal situation compared to my 991 losing heat in the cabin, or my exhaust getting stuck in "loud" mode.
Anyways, just my $0.02.....
I've had 3 solenoids replaced in the past 10 months, all separate instances where I had to go back to the service department to get fixed.
Now compare that to the recent global recall for a "potential" failure of some unknown facet of the hood latch mechanism, as covered in a previous thread on this and other forums: Porsche recalling 4,400 911, Boxster and Cayman models over hood latches I can't recall a single case on this or the other 3 forums I participate in where someone has reported any problem with their frunk or engine cover latches....
But then, maybe it is purely one of liability? I can understand how a hood latch failing while under speed is potentially a much more costly legal situation compared to my 991 losing heat in the cabin, or my exhaust getting stuck in "loud" mode.
Anyways, just my $0.02.....
I've had 3 solenoids replaced in the past 10 months, all separate instances where I had to go back to the service department to get fixed.
Last edited by plenum; Nov 12, 2014 at 07:29 AM. Reason: fixed typo
It does not seem to make much sense to me. If a car has one occurrence, it would seem prudent to replace all the old generation parts. My build was 7/2013 and it appears that my car has all the first generation COVs.
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Joined: Oct 2013
Posts: 665
From: SoCal
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I wish I could aquire a bad COV to put on the symposer ; )
Also, is the intake flap just a sound thing or does it have performance value?
How would one know if it was not working?
I do plan to have all my COV changed, now that it appears there is a new version that resolves the issue.
I think the thing to do is buy 8 COV and when one fails (or you get a service) ask the Shop Foreman to replace the other COV (with your new COV) and agree to a reasonable price for that labor.
Could a COV cause the AC to blow hot air? Thats my current issue.
I wish I could aquire a bad COV to put on the symposer ; )
Also, is the intake flap just a sound thing or does it have performance value?
How would one know if it was not working?
I do plan to have all my COV changed, now that it appears there is a new version that resolves the issue.
I think the thing to do is buy 8 COV and when one fails (or you get a service) ask the Shop Foreman to replace the other COV (with your new COV) and agree to a reasonable price for that labor.
I wish I could aquire a bad COV to put on the symposer ; )
Also, is the intake flap just a sound thing or does it have performance value?
How would one know if it was not working?
I do plan to have all my COV changed, now that it appears there is a new version that resolves the issue.
I think the thing to do is buy 8 COV and when one fails (or you get a service) ask the Shop Foreman to replace the other COV (with your new COV) and agree to a reasonable price for that labor.
Last edited by 991carreradriver; Nov 12, 2014 at 10:02 AM.
Registered User
Joined: Feb 2012
Posts: 313
From: Mid-Atlantic
Rep Power: 33
Could a COV cause the AC to blow hot air? Thats my current issue.
I wish I could aquire a bad COV to put on the symposer ; )
Also, is the intake flap just a sound thing or does it have performance value?
How would one know if it was not working?
I do plan to have all my COV changed, now that it appears there is a new version that resolves the issue.
I think the thing to do is buy 8 COV and when one fails (or you get a service) ask the Shop Foreman to replace the other COV (with your new COV) and agree to a reasonable price for that labor.
I wish I could aquire a bad COV to put on the symposer ; )
Also, is the intake flap just a sound thing or does it have performance value?
How would one know if it was not working?
I do plan to have all my COV changed, now that it appears there is a new version that resolves the issue.
I think the thing to do is buy 8 COV and when one fails (or you get a service) ask the Shop Foreman to replace the other COV (with your new COV) and agree to a reasonable price for that labor.
I too, have the same question about the intake flap.
Regarding the new version COV (part # ending in F) there is a report on the "other" board of someone already have had a failure of an "F" valve.
I wonder if we now need a fifth generation "G" valve?
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Joined: Feb 2013
Posts: 14
From: Bournemouth
Rep Power: 0
Cov
My experience has been:
1) internal heating no longer working (ie only cold) - turned out to be COV fault
2) PSE always loud - ignored the problem
3) error on dashboard 'coolant fault go to garage' - 2 COVs at fault, fixed issue 2
Just waiting for the other COVs to fail!
Dealer has been great, sorted out the problems within a day and gone out their way to provide a loan car etc. It appears dealers are restricted in terms of stocking COVs until the fault is diagnosed as a COV fault, I guess limited supply of these units.
Nick
1) internal heating no longer working (ie only cold) - turned out to be COV fault
2) PSE always loud - ignored the problem
3) error on dashboard 'coolant fault go to garage' - 2 COVs at fault, fixed issue 2
Just waiting for the other COVs to fail!
Dealer has been great, sorted out the problems within a day and gone out their way to provide a loan car etc. It appears dealers are restricted in terms of stocking COVs until the fault is diagnosed as a COV fault, I guess limited supply of these units.
Nick
My experience has been: 1) internal heating no longer working (ie only cold) - turned out to be COV fault 2) PSE always loud - ignored the problem 3) error on dashboard 'coolant fault go to garage' - 2 COVs at fault, fixed issue 2 Just waiting for the other COVs to fail! Dealer has been great, sorted out the problems within a day and gone out their way to provide a loan car etc. It appears dealers are restricted in terms of stocking COVs until the fault is diagnosed as a COV fault, I guess limited supply of these units. Nick
Last edited by 991carreradriver; Nov 16, 2014 at 08:05 AM.
