What is the current state of the 'engine stumble' issue?
#167
Burning Brakes
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One is a hiccup right at 3000 RPM when accelerating through that point - it's where the VarioCam changes position. But the other is felt when trying to maintain a constant velocity or accelerate slowly near the 2300-2500 RPM range.
I have both so I know they feel completely different.
#170
Rennlist Member
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The GT4 uses the 3.8 NA, which is the 991.1 S engine. Panorama (July 2016 issue, p.47) did a GT4 v. GTS review, in which I read the following: "The only fly in the ointment is an annoying stumble in the mid-range, which was persistent but somewhat intermittent. In this era of ultra-precise engine management technology, we can only conclude that such an obvious imperfection must somehow be intentional and/or an unavoidable by product of EPA compliance"
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
#171
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I still feel like I got the 2500 stumble regularly prior to throttle body replacement and almost never after. Has anyone that's had the TB replaced (stock or aftermarket) had the stumble continue?
#172
Three Wheelin'
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I know this engine stumble is a mystery. Some cars have it and some not. Could this stumble have anything to do with how the engine was broken in? The reason I ask is that my wife's car does not have the stumble. The car is a 2016 C2 manual. She broke the car in literally by the book. The revs never went over 4K for the first 2000 miles. Is there any correlation here?
#173
Burning Brakes
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I know this engine stumble is a mystery. Some cars have it and some not. Could this stumble have anything to do with how the engine was broken in? The reason I ask is that my wife's car does not have the stumble. The car is a 2016 C2 manual. She broke the car in literally by the book. The revs never went over 4K for the first 2000 miles. Is there any correlation here?
#175
Rennlist Member
Thread Starter
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The GT4 uses the 3.8 NA, which is the 991.1 S engine. Panorama (July 2016 issue, p.47) did a GT4 v. GTS review, in which I read the following: "The only fly in the ointment is an annoying stumble in the mid-range, which was persistent but somewhat intermittent. In this era of ultra-precise engine management technology, we can only conclude that such an obvious imperfection must somehow be intentional and/or an unavoidable by product of EPA compliance"
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
J
#176
Rennlist Member
Thread Starter
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I know this engine stumble is a mystery. Some cars have it and some not. Could this stumble have anything to do with how the engine was broken in? The reason I ask is that my wife's car does not have the stumble. The car is a 2016 C2 manual. She broke the car in literally by the book. The revs never went over 4K for the first 2000 miles. Is there any correlation here?
J
#177
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The GT4 uses the 3.8 NA, which is the 991.1 S engine. Panorama (July 2016 issue, p.47) did a GT4 v. GTS review, in which I read the following: "The only fly in the ointment is an annoying stumble in the mid-range, which was persistent but somewhat intermittent. In this era of ultra-precise engine management technology, we can only conclude that such an obvious imperfection must somehow be intentional and/or an unavoidable by product of EPA compliance"
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
Maybe this is why the problem has never been solved. Where is a VW programmer when you need one?
If that were the case, one would assume the defect would affect all 991 owners, not just those of us that drew the short straw.
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#178
Rennlist Member
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The point of my post was to let the participants (especially those with the problem) know that a national, well respected periodical recognize that it exists.
#179
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What the magazine is saying that the gt4 might have been "sabotaged" to not take away from the more expensive Porsches. They didn't know the more expensive ones have it, too.
#180
Addict
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I know this engine stumble is a mystery. Some cars have it and some not. Could this stumble have anything to do with how the engine was broken in? The reason I ask is that my wife's car does not have the stumble. The car is a 2016 C2 manual. She broke the car in literally by the book. The revs never went over 4K for the first 2000 miles. Is there any correlation here?
Wonder if the 991.2 has these issues resolved......