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But for reference, pic below indicates location of all COVs on the 991:
(Ignore the red notation...).
Back in Nov 2015 Porsche Tech Bulletin 35/15 ENU 2456 described spare parts requirements for change-over valves on the 991. Specifically the bulletin stated "Different change-over valves are now used, depending on the installation position." Whatever that means! The bulletin directs technician to check updated PET catalog for new part number.
As for how many on a 991, # ranges from 7 to 10 per below:
1. Air Cleaner Flap
2. Acoustic Simulator
3. Heater Shut-Off Valve
4. Exhaust Flaps
5. Coolant Shut-Off Valve on Engine Bypass Circuit
6. Tuning Flap
7. Shut-Off Valve on Heat Exchanger for Gear Wheel Set Oil
8. Shut-Off Valve for Clutch Fluid Heat Exchanger (PDK ONLY)
9. Tuning Flap (X-51 Power Kit ONLY)
10. Tuning Flap (X-51 Power Kit ONLY)
#9 and 10 are not a mistake on my part.... X-51 has multiple tuning flaps apparently.
Plenum, so just leave well enough alone until/if one/few of them fail??
STG- as far as I can tell there hasn't been any new campaigns to proactively replace COVs, so I do believe there is a "replace when fail" approach.... The last campaign if you'll remember was back in I think 2013 covering the earliest 991 birth dates, and there hasn't been one since.
I think that the reluctance to start a proactive campaign is that many of the failures have been attributed to environmental conditions (esp water entering the COV) which may be related to region the car is operated, and even then it is hit-or-miss whether a car would encounter the conditions to cause failure. Partly my educated guess only....
FWIW, I am attending a Porsche tech tactics session in about a week at the regional tech training facility here in PA -- I usually meet-up with some of the training staff (they hide the techs-in-training!) while there and if I remember I will ask them about the COVs... I may be distracted by the 991.2 and GT4 technical classes and forget about the 991 tho! LOL
I was thinking about buying a spare solenoid for my tool kit, but this doesn't look like a roadside repair!
I'd have to verify with the WM's, but at a minimum you would have to remove the rear taillight and probably bumper cover to reach even the COVs closest to the rear. While you may be able to get to them in an emergency, this is better-off something you do in the garage.... And honestly, these are not parts that will strand you on the road if they fail. You may not have heat, the exhaust may be louder, and perhaps you'll see some other cooling system warnings, but Porsche isn't proactively replacing these parts for the very fact that they won't immediately cause more damage when they fail. YMMV
I have to be honest with you; who cares? Drive your car, enjoy it, when it breaks take it in and have it looked at. 6 months before the warranty expires sit down with your service advisor and have a candid conversation about what you should look for before the warranty runs out. I owned and drove a 996 c2 cab for 7 years with zero issues out of warranty. I owned and drove a 01 996 turbo for 10 years with zero issues out of warranty. Both should be basket cases if you believe what you read on the internet.
My point is that every modern car has a list of issues and you can drive yourself crazy working about it. Just enjoy your ride!
My car was built in Nov '12, had the campaign to replace the COVs in Sept '13, and in the fall of '14 I had heater problem (COV replaced) and then PSE problem (COV replaced). So even with having the campaign done, I still had two COV-related problems.
On the plus side, that was well over a year ago and I haven't had any problems since then.
I updated my new part post above. New version of COV's require a NEW wiring harness that they plug into as well. Like a small 1.5" cord with two plugs on each end. The COV one end, and the other plugs into the car.
The tech who works on my car noted condensation can occur with the car and parts heating/cooling. Condensation seems to be the culprit with the previous COV failures.
I updated my new part post above. New version of COV's require a NEW wiring harness that they plug into as well. Like a small 1.5" cord with two plugs on each end. The COV one end, and the other plugs into the car.
The tech who works on my car noted condensation can occur with the car and parts heating/cooling. Condensation seems to be the culprit with the previous COV failures.
Did you change all of them (it's like 7 or 8 isn't it)?
Did you change all of them (it's like 7 or 8 isn't it)?
6 for manual and no PSE
Add one each if you have PDK and PSE which would be 7 or a grand total of 8.
Mind you, these are covered under warranty. They did a voluntary replacement on some of them (not all) on the early 2012.5/2013 cars, but that was for the second version. They just now came out with the third version for the 991.1 because they are still having failures. Seems to be related to condensation. They went with a new manufacturer this time. I assume none of the new 2016's even have this version. Not 100% sure though. I'd have to check.
Have my car in for other work, and just decided to change them all out as a preventative measure at my cost. My car is still under warranty. Just don't feel like dealing with one or more failures. I think for some, you might not necessarily notice either from what I've read in this thread.
Two common ones that fail are for the PSE and heating system for the cabin.
STG, do you happen to know or have an idea when the new ones started to be installed at the factory? I had a coolant warning trigger last summer that included a noticeable change in the exhaust tone. Could this have been a COV? I was told that a hose came loose -- didn't make compete sense to me, but I've had no problems since then.
02-23-2016, 11:20 AM
The bulletin directs technician to check updated PET catalog for new part number.
