What is the current state of the 'engine stumble' issue?
#361
Three Wheelin'
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Oh, just the defective reverse switch. They replaced the tranny in May, but the lockout for 7th gear works too well - it won't let me into 7th. Replacement to fix that issue this time, lol.
#362
#363
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for others here looking to replace their Throttle bodies on 991.1 cars. You can get 15% off when you sign up for emails and free shipping. This is the best price I have seen. My part was dropped shipped to me directly from Bosch USA.
https://shop.advanceautoparts.com/p/...m_content=ITEM
https://shop.advanceautoparts.com/p/...m_content=ITEM
#364
Rennlist Member
#365
Three Wheelin'
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I believe they're all 82mm. I know that when I was trying to find the lowest-priced Bosch unit I also stumbled (pun intended) on an aftermarket company that takes the factory TB and modifies it to be an 86mm effective size, but I can't recall who that is now.
#366
Three Wheelin'
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I replaced my throttle body last night with the Bosch equiv. part. While I was in there, I also fixed the brake light wiring in my wing as it became severed from age/use. I also changed the oil while I had the car apart as the filter is so much easier to get to when the wing is out of the way. Total about 6 hours of work taking my time, steam cleaning as I took things like the airbox out.
The car feels 100% completely new. There is no hesitation, no stumble. All of the jerkiness in that 2,000 to 3,000 rpm range is completely, entirely gone.
This is just one drive, about 60 km. But, the difference was immediately noticeable.
For a $200~ part, I think folks have very little to lose by trying a new throttle body. It's really not a difficult item to replace!
The car feels 100% completely new. There is no hesitation, no stumble. All of the jerkiness in that 2,000 to 3,000 rpm range is completely, entirely gone.
This is just one drive, about 60 km. But, the difference was immediately noticeable.
For a $200~ part, I think folks have very little to lose by trying a new throttle body. It's really not a difficult item to replace!
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CSK 911 C4S (10-25-2021),
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#367
Rennlist Member
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I don't drive my 13 991.1 very much anymore but every time I drive it it feels new, throttle response is crisp and PDK is on point.
Does anyone know with time does the car's computer refresh it's driving parameters or is it all in my head.
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#368
#369
#370
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I had a unstable idle...im pretty sure that the butterfly can open or close briefly and product this hesitation.
The tech tested it and found that the respond was bad and erratic
#371
Three Wheelin'
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Just a quick update. I managed to sneak in a trip to the mountains today and did about 400 km of driving (rained and snowed on me, so the car is dirtier than it's ever been!). There are some instances of what could be attributed to the "stumble" - especially at 2,200 rpm~. That said, it's still a vast improvement over where it was before the throttle body replacement.
I'm probably going to replace the variocam solenoids as well, if anything because I just want to understand this problem as well as I can. I'll have all winter to contemplate that as I'll probably get the car put away in the next week or two.
I'm probably going to replace the variocam solenoids as well, if anything because I just want to understand this problem as well as I can. I'll have all winter to contemplate that as I'll probably get the car put away in the next week or two.
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Porsche_nuts (10-25-2021)
#372
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Just a quick update. I managed to sneak in a trip to the mountains today and did about 400 km of driving (rained and snowed on me, so the car is dirtier than it's ever been!). There are some instances of what could be attributed to the "stumble" - especially at 2,200 rpm~. That said, it's still a vast improvement over where it was before the throttle body replacement.
I'm probably going to replace the variocam solenoids as well, if anything because I just want to understand this problem as well as I can. I'll have all winter to contemplate that as I'll probably get the car put away in the next week or two.
I'm probably going to replace the variocam solenoids as well, if anything because I just want to understand this problem as well as I can. I'll have all winter to contemplate that as I'll probably get the car put away in the next week or two.
Ill Keep you in touch
#373
Three Wheelin'
#374
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I had to change 2 of the four.. I had multiple misfire and the car was barely drivable..
BMW tells that they are wearable item..
Look at this thread https://rennlist.com/forums/991/1207...wear-item.html
I had to change 2 of the four.. I had multiple misfire and the car was barely drivable..
BMW tells that they are wearable item..
Look at this thread https://rennlist.com/forums/991/1207...wear-item.html
#375
Rennlist Member
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koala (10-26-2021)