I'm sick...think my car is developing "The Stumble"
#76
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Hasn't Porsche said this is "normal behavior" ![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Good luck guys. This subject has been talked about for years. Someone needs to get to the bottom of it! It's been toooooo long. I mean, can't a competent race shop figure this out? Can't be that complicated.
If a shop is able to figure out putting in an R transmission in a GT3 RS, they surely can figure out a stumble issue![popcorn](https://rennlist.com/forums/images/smilies/popcorn.gif)
![Roll Eyes (Sarcastic)](https://rennlist.com/forums/images/smilies/rolleyes.gif)
Good luck guys. This subject has been talked about for years. Someone needs to get to the bottom of it! It's been toooooo long. I mean, can't a competent race shop figure this out? Can't be that complicated.
If a shop is able to figure out putting in an R transmission in a GT3 RS, they surely can figure out a stumble issue
![popcorn](https://rennlist.com/forums/images/smilies/popcorn.gif)
#77
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Report for day two. No stumble at all.
just for frame of reference my stumble before was extremely noticeable especially in second gear. The stumble felt like a misfire or a cough where it's severely affected the performance of the vehicle at 2500 RPM. It did go away sometimes or at certain throttle angles, but I could reproduce it pretty much anytime I wanted to at very slight throttle angle. Some days were worse than others. For what seems to be no rhyme or reason.
just for frame of reference my stumble before was extremely noticeable especially in second gear. The stumble felt like a misfire or a cough where it's severely affected the performance of the vehicle at 2500 RPM. It did go away sometimes or at certain throttle angles, but I could reproduce it pretty much anytime I wanted to at very slight throttle angle. Some days were worse than others. For what seems to be no rhyme or reason.
![Mad](https://rennlist.com/forums/images/smilies/mad.gif)
#78
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Good luck guys. This subject has been talked about for years. Someone needs to get to the bottom of it! It's been toooooo long. I mean, can't a competent race shop figure this out? Can't be that complicated.
If a shop is able to figure out putting in an R transmission in a GT3 RS, they surely can figure out a stumble issue![popcorn](https://rennlist.com/forums/images/smilies/popcorn.gif)
If a shop is able to figure out putting in an R transmission in a GT3 RS, they surely can figure out a stumble issue
![popcorn](https://rennlist.com/forums/images/smilies/popcorn.gif)
Did Oswald act alone?
Where's Hoffa buried?
WTF causes the stumble?
#79
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#81
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Tomorrow is Saturday, somebody go to your local parts store and pick up two pre-catalytic converter oxygen sensors and install them. Report back the results.
#82
#83
Burning Brakes
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No local place stocks the Bosch O2 sensor I need. I'll have to order it online. Looking at $248 for both, plus I'll need the slotted 22mm socket adapter. Did you have any issues getting the old ones out? What torque did you use to tighten the new ones in?
#84
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#85
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you can try your local Porsche dealer but you'll spend probably double. My local Porsche dealer it will match online Porsche dealer prices. I go to Sunset Porsche and show them that price and they will match it. I believe sunset sells them for about $185 apiece. I do have the slotted wrench for getting out the O2 sensors but the slot is too small for our multi wire 02 sensors so I just use a regular wrench . I used the German standard of Gundentite.
#88
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Yep if that fits your vehicle, order two of them. One for each header.
#89
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I doubt both are bad get one and try it on one side first then the other see what happens.
#90
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