Vario Cam Solenoid a wear item?
The following 3 users liked this post by AdamSanta85:
#19
Burning Brakes
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Class5Kayaker (08-11-2020)
#20
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@rnl Could you please be so kind as to take a minute to explain your exact symptoms to the rest of us.
You wrote "The stumbling issue occurs at higher revs....."
I'm not aware of anyone stumbling at higher revs, so are you describing your issue or did your symptoms occur at 2500rpm and below?
You also wrote "..for this problem the car only was smooth at rpm greater than 2500". This implies that you had an issue in the 2k-3000 rpm range. Is that correct?
Most stumblers complain about a stumble (non-linear power delivery) between 2500-2800 rpm and not at higher revs.
Thanks in advance..
You wrote "The stumbling issue occurs at higher revs....."
I'm not aware of anyone stumbling at higher revs, so are you describing your issue or did your symptoms occur at 2500rpm and below?
You also wrote "..for this problem the car only was smooth at rpm greater than 2500". This implies that you had an issue in the 2k-3000 rpm range. Is that correct?
Most stumblers complain about a stumble (non-linear power delivery) between 2500-2800 rpm and not at higher revs.
Thanks in advance..
The following users liked this post:
Class5Kayaker (08-11-2020)
#21
Burning Brakes
Thread Starter
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@rnl Could you please be so kind as to take a minute to explain your exact symptoms to the rest of us.
You wrote "The stumbling issue occurs at higher revs....."
I'm not aware of anyone stumbling at higher revs, so are you describing your issue or did your symptoms occur at 2500rpm and below?
You also wrote "..for this problem the car only was smooth at rpm greater than 2500". This implies that you had an issue in the 2k-3000 rpm range. Is that correct?
Most stumblers complain about a stumble (non-linear power delivery) between 2500-2800 rpm and not at higher revs.
Thanks in advance..
You wrote "The stumbling issue occurs at higher revs....."
I'm not aware of anyone stumbling at higher revs, so are you describing your issue or did your symptoms occur at 2500rpm and below?
You also wrote "..for this problem the car only was smooth at rpm greater than 2500". This implies that you had an issue in the 2k-3000 rpm range. Is that correct?
Most stumblers complain about a stumble (non-linear power delivery) between 2500-2800 rpm and not at higher revs.
Thanks in advance..
This is not like the undiagnosed stumble encountered by some.
Car now idles smoothly,. accelerates crisply
#22
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Thanks for your response.
#23
Instructor
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The symptoms for me were the misfire codes on one side of the engine, and engine stuttering when idling and starting from a stop. It came and went, but finally got sick of it like two weeks ago so just put aside an hour to get to it. As said, only needed 30 minutes from wheels up to wheels down.
So far, about 500 miles and drives smooth. I noticed before when the I stopped a little harder, the PDK downshifted with noticeable shifts. Now, it smooth up and down. So, it might be all related as part of engine management.
#24
Three Wheelin'
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Very interesting. I have the low speed/from a stop stumble. I am pondering doing this. Would cost me about the same as bringing it to the dealer and having the mess with it for an hour and then tell me they can't find a problem. Anyone else cure a low speed stumble with this repair?
#25
Instructor
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Very interesting. I have the low speed/from a stop stumble. I am pondering doing this. Would cost me about the same as bringing it to the dealer and having the mess with it for an hour and then tell me they can't find a problem. Anyone else cure a low speed stumble with this repair?
#26
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No codes for me. Just hesitates from a stop and I feel like low rpm torque is wimpy and I could swear it was more torquey at lower revs. Mine is a 3.8 with 62,000 miles. High rpm no problem, she screams and throws me back in the seat. Noticed this issue about 5,000 miles ago.
#27
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I have felt like my 14 C4S has had a stumble below 4k rpm under light to medium throttle. No codes thrown, but it just feels to hesitate during acceleration. There is also an audible skip or cough that can be replicated pretty much on command when the throttle is changed from light to medium in the 2500-3500 range. Above 4k the car screams and there is absolutely no hesitation but I would love for the car to be smoother under 4k rpm. I have thought maybe it needs a PDK clutch, but I may change these as it seems like an easy DIY. Thanks for posting!
#28
Burning Brakes
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No codes for me. Just hesitates from a stop and I feel like low rpm torque is wimpy and I could swear it was more torquey at lower revs. Mine is a 3.8 with 62,000 miles. High rpm no problem, she screams and throws me back in the seat. Noticed this issue about 5,000 miles ago.
#29
Burning Brakes
Thread Starter
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I have felt like my 14 C4S has had a stumble below 4k rpm under light to medium throttle. No codes thrown, but it just feels to hesitate during acceleration. There is also an audible skip or cough that can be replicated pretty much on command when the throttle is changed from light to medium in the 2500-3500 range. Above 4k the car screams and there is absolutely no hesitation but I would love for the car to be smoother under 4k rpm. I have thought maybe it needs a PDK clutch, but I may change these as it seems like an easy DIY. Thanks for posting!
I brought my car in to the dealer when I noticed this happening and probably because no codes were present they said - bad gas...the hiccup in the 2500-3500 range is key
#30
Instructor
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yes, because it doesn't always happen, you might think it's something else like "bad gas" or "cold morning" etc. I had it happen when right after getting off highway. It stuttered and drove strange. I pulled off and then thought maybe it was bad gas. Filled up on Sunoco Ultra and right after it ran better. So I thought bad gas. Then on way home it acted up again and CEL came on. I'm sure there are other causes for hesitation, but this is probably easiest to fix.