I'm sick...think my car is developing "The Stumble"
07-24-2017, 10:50 AM
#123
Rennlist Member
Thanks pfan!! I agree, the arms look like you just got out of a knife fight! HA! But worth it! The techs these days don't change anything unless there is a code, probably don't even look at live fuel trim data or anything.
Installed the new O2 sensors this weekend (and yes, it took most of the weekend). Bottom line ........ it feels like a new engine! After 150 miles of rigorous testing, the stumble IS GONE, at least for now. I'm like a kid on Christmas morning who hit the jackpot. Not only is the stumble gone, but the engine feels much smoother throughout the entire operating range.
ChicagoSpeed996: I can't thank you enough for providing the info on this.
I'd all but given up on ever again having a non-stumbling car.
And to PCNA and your dealers:
…………………./´¯/)
………………..,/¯../
………………./…./
…………./´¯/’…’/´¯¯`·¸
………./’/…/…./……./¨¯\
……..(‘(…´…´…. ¯~/’…’)
………\……………..’…../
……….”…\………. _.·´
…………\…………..(
…………..\………….\…
Thanks for not lifting a finger to attempt to resolve this issue. (I'll lift mine instead). Four years of not being able to completely enjoy what an amazing car the 991 is. Totally WORTHLESS support. Shameful.
And finally, to those of you who might be considering replacing your O2 sensors: It's an easy job, once you get the rear bumper and airbox off.
Then be prepared for a couple of hours trying to figure out how to route the cables. Your hands and forearms will come out looking like you've been in a knife fight. 
ChicagoSpeed996: I can't thank you enough for providing the info on this.
I'd all but given up on ever again having a non-stumbling car.
And to PCNA and your dealers:
…………………./´¯/)
………………..,/¯../
………………./…./
…………./´¯/’…’/´¯¯`·¸
………./’/…/…./……./¨¯\
……..(‘(…´…´…. ¯~/’…’)
………\……………..’…../
……….”…\………. _.·´
…………\…………..(
…………..\………….\…
Thanks for not lifting a finger to attempt to resolve this issue. (I'll lift mine instead). Four years of not being able to completely enjoy what an amazing car the 991 is. Totally WORTHLESS support. Shameful.
And finally, to those of you who might be considering replacing your O2 sensors: It's an easy job, once you get the rear bumper and airbox off.
Then be prepared for a couple of hours trying to figure out how to route the cables. Your hands and forearms will come out looking like you've been in a knife fight.
07-24-2017, 01:50 PM
#124
pfan, this is amazing. Now with two data points this is very compelling and I cannot wait to provide a third data point! I'm so happy for you.
Can you provide some details about the installation? Do you think you really needed to remove the rear bumper? I have no problem doing that, but I am just curious if it's really necessary. A few weeks ago I did the engine air filters (so I had to remove the bumper), and did the spark plugs (so I worked around where the O2 sensors actually screw into the exhaust), but I never saw the other end of the O2 sensor wire plug...
The worst part of the bumper removal was just making sure the rear lights were back into position without moving those leveling nuts... so it would be awesome to not deal with that again
.
Can you provide some details about the installation? Do you think you really needed to remove the rear bumper? I have no problem doing that, but I am just curious if it's really necessary. A few weeks ago I did the engine air filters (so I had to remove the bumper), and did the spark plugs (so I worked around where the O2 sensors actually screw into the exhaust), but I never saw the other end of the O2 sensor wire plug...
The worst part of the bumper removal was just making sure the rear lights were back into position without moving those leveling nuts... so it would be awesome to not deal with that again
.It's a pain, but the results were well worth the effort! Best of luck.
07-24-2017, 03:13 PM
#125
Burning Brakes
Unfortunately, it appears the bumper, spoiler, and airbox need to come off to access the connector which is just outboard of the dynamic engine mount. Routing the wiring cable down the side of the engine compartment is the real challenge. Good video here detailing removal of bumper and airbox.
It's a pain, but the results were well worth the effort! Best of luck.
It's a pain, but the results were well worth the effort! Best of luck.
No pain no gain! Gotta do this.
07-24-2017, 06:48 PM
#126
I think I'm going to cry!!!
ChicagoSpeed - Can I have your babies??
There is actual light at the end of this mother of a tunnel...
ChicagoSpeed - Can I have your babies??
There is actual light at the end of this mother of a tunnel...
07-24-2017, 08:00 PM
#127
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
07-24-2017, 08:01 PM
#128
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
Installed the new O2 sensors this weekend (and yes, it took most of the weekend). Bottom line ........ it feels like a new engine! After 150 miles of rigorous testing, the stumble IS GONE, at least for now. I'm like a kid on Christmas morning who hit the jackpot. Not only is the stumble gone, but the engine feels much smoother throughout the entire operating range.
ChicagoSpeed996: I can't thank you enough for providing the info on this.
I'd all but given up on ever again having a non-stumbling car.
And to PCNA and your dealers:
…………………./´¯/)
………………..,/¯../
………………./…./
…………./´¯/’…’/´¯¯`·¸
………./’/…/…./……./¨¯\
……..(‘(…´…´…. ¯~/’…’)
………\……………..’…../
……….”…\………. _.·´
…………\…………..(
…………..\………….\…
Thanks for not lifting a finger to attempt to resolve this issue. (I'll lift mine instead). Four years of not being able to completely enjoy what an amazing car the 991 is. Totally WORTHLESS support. Shameful.
And finally, to those of you who might be considering replacing your O2 sensors: It's an easy job, once you get the rear bumper and airbox off. Then be prepared for a couple of hours trying to figure out how to route the cables. Your hands and forearms will come out looking like you've been in a knife fight.
ChicagoSpeed996: I can't thank you enough for providing the info on this.
I'd all but given up on ever again having a non-stumbling car.
And to PCNA and your dealers:
…………………./´¯/)
………………..,/¯../
………………./…./
…………./´¯/’…’/´¯¯`·¸
………./’/…/…./……./¨¯\
……..(‘(…´…´…. ¯~/’…’)
………\……………..’…../
……….”…\………. _.·´
…………\…………..(
…………..\………….\…
Thanks for not lifting a finger to attempt to resolve this issue. (I'll lift mine instead). Four years of not being able to completely enjoy what an amazing car the 991 is. Totally WORTHLESS support. Shameful.
And finally, to those of you who might be considering replacing your O2 sensors: It's an easy job, once you get the rear bumper and airbox off.
Then be prepared for a couple of hours trying to figure out how to route the cables. Your hands and forearms will come out looking like you've been in a knife fight.
07-24-2017, 08:06 PM
#129
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GA Skin Doc (05-07-2020)
07-24-2017, 08:10 PM
#130
Burning Brakes
Point of reference: Today my local Porsche dealer quoted me $850 for the labor alone (5 hours) for swapping out both O2 sensors. Figure $500+ more for the two sensors at dealer prices.
I plan to do my own, but this is just for anyone else without the inclination for a DIY solution.
I plan to do my own, but this is just for anyone else without the inclination for a DIY solution.
07-24-2017, 08:10 PM
#131
Race Director
Originally Posted by Needsdecaf
You're not kidding. Only thing bigger would be Dunedin completely solving the GT3 finger follower wear issue.
This "normal" behavior as noted by some regional Porsche reps is such a joke. They should be embarrassed of themselves.
07-24-2017, 09:34 PM
#132
I've got a 2016 981S that's had the problem since day 1. I'll be trying the O2 fix, but this (and PCNA's lousy customer service) makes me wonder if there isn't an emission issue here. After diesel-gate I wouldn't put anything past these guys. Anyone have the ability to do an actual emissions test like the one that identified the diesel cheaters?
07-24-2017, 09:39 PM
#133
These guys are $114.00
Amazing the mark ups on these parts. Some dealers getting almost $300.00
What a joke.
http://www.importecwarehouse.com/mob...101-SF-14.htm=
Attachment 1188948
Amazing the mark ups on these parts. Some dealers getting almost $300.00
What a joke.
http://www.importecwarehouse.com/mob...101-SF-14.htm=
Attachment 1188948
07-24-2017, 09:43 PM
#134
Race Director
Originally Posted by neurotichamster8
thanks STG! will this work on a 991.1 GTS also?
Luke Rogers
Porsche Parts Consultant
Toll Free: 800.346.0182
Office: 503.644.2012 option 2
LukeRogers@sunsetimports.com
Sunset Porsche
07-24-2017, 11:09 PM
#135
You bring up an excellent point. My stumble was also from around day 1. I've always been curious as to why Porsche absolutely refuses to even acknowledge the problem. Hmmm.