Weird stumble/jerk at 2800 rpm.
#1
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a car that can't do the throttle reset.
Weird stumble/jerk at 2800 rpm.
04 c32.
about 40k.
Strange... when at a dead stop, and give pretty good acceleration (but nowhere near full throttle) the car takes off fine, but then right at about 2800 rpm the car thuds and trips the traction control light. It doesn't feel like the rear is breaking loose. It feels almost like the car is shifting into second, and the gear change is really hard. However, it is happening in first.. cause I tried just staying on it, and I was able to go higher in the rpm range without issue in first. Only happens when I push the car semi hard. Think of it as when you are in a two lane road that merges into one lane.. you want to be first, but don't need to go all out.
I did a search and many seem to have a similar experience at 1500 rpm being glycol contamination. Is this what I should be looking at as well? Any thoughts appreciated. Thanks.
about 40k.
Strange... when at a dead stop, and give pretty good acceleration (but nowhere near full throttle) the car takes off fine, but then right at about 2800 rpm the car thuds and trips the traction control light. It doesn't feel like the rear is breaking loose. It feels almost like the car is shifting into second, and the gear change is really hard. However, it is happening in first.. cause I tried just staying on it, and I was able to go higher in the rpm range without issue in first. Only happens when I push the car semi hard. Think of it as when you are in a two lane road that merges into one lane.. you want to be first, but don't need to go all out.
I did a search and many seem to have a similar experience at 1500 rpm being glycol contamination. Is this what I should be looking at as well? Any thoughts appreciated. Thanks.
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C32 AMG
#7
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Clutches, like everything else, show signs of wear as time goes on. Some owners feel it others don't. When you feel this jerk, do you sometimes hear a slight churp by chance?
I'm used to it on my car. I can actually feel, at low RPMs, when the blower engages as it actually strains the engine a bit till the boost picks up. Kinda nutty but that makes sense since it takes power to make power with a blower.
I'm used to it on my car. I can actually feel, at low RPMs, when the blower engages as it actually strains the engine a bit till the boost picks up. Kinda nutty but that makes sense since it takes power to make power with a blower.
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#9
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2003 porsche 996 turbo
s/c actually engages below 1200 rpm. if you raise the hood and have someone watch the clutch then raise the rpm they will see it engage.
sounds like a tranny issue. try a filter swap and fluid flush
sounds like a tranny issue. try a filter swap and fluid flush
#11
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This can't be normal it is far too rough a feeling.
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white and whiter
hard to tell if it's belt slip causing the jerk or clutch slip. if the clutch physically looks fine I would change the belt and see what happens. It also may be the belt tensioner if it's the belt slip.
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2008 A8L, 2002 996TT X50, 2009 X5
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#17
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I don't know how much help this will be but, I have the exact same issue, intermittently. Here was the thread I started on this issue:
https://mbworld.org/forums/c32-amg-c...hirp-saga.html
Try Jerry's suggestion to disconnect the S/C to determine if it is, in fact, the clutch. It takes 30 seconds to diagnose it with his suggestion.
I purchased a spare S/C for less than a new clutch assembly would have run. I am keeping it at the ready for when the clutch does give up the ghost or it becomes so annoying I can't stand it any more.
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a car that can't do the throttle reset.
Thanks a ton guys! Appreciate the link! Gonna read it now. I can't wrench to save my life. But I am gonna do some searching and hopefully come up with something. Will report back if I figure anything new out, including a resolution.
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2003 porsche 996 turbo
The supercharger can engage as soon as 1200 but won't, if it doesn't need to, till approx 2,800 RPM—after that point the ecu turns on and keeps it on till you let off the throttle for an extended period of time. It all depends on the engine load.
I know, sometimes my car feels like I'm popping a clutch as if I had a manual gearbox. Sometimes it's just a slight blip. Do you know anyone else who has a C32 or even an SLK32? Drive their car the same way and I betcha you'll feel it.
I know, sometimes my car feels like I'm popping a clutch as if I had a manual gearbox. Sometimes it's just a slight blip. Do you know anyone else who has a C32 or even an SLK32? Drive their car the same way and I betcha you'll feel it.
i have a slk32 and have never experienced this in my car. its a smooth as silk and when stomped on the power is instant.
#21
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check out woody's thread on this issue. he shows were the s/c comes on at approx 1200 and stays engaged until under the same rpm. for all intensive purposes the s/c stays engaged while driving.
i have a slk32 and have never experienced this in my car. its a smooth as silk and when stomped on the power is instant.
i have a slk32 and have never experienced this in my car. its a smooth as silk and when stomped on the power is instant.
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2003 porsche 996 turbo
I know which thread you are talking about. You are missing the point though. Do you drive your car with your foot on the brake? I don't. What he demonstrates is that under a load (i.e. foot on the brake) that the ECU wants to turn the blower on. If you pu$$y foot the throttle from a dead stop with the tranny in first you can get to ~2,800 RPM before the blower engages. Since you car's clutch operates smoother you may not feel this.
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#23
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Test drive.
Reverse process, utilizing thumb and index finger.
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#24
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a car that can't do the throttle reset.
No wrenching needed. Just put your thumb on one side of the clip and your index finger on the other side. Now, apply inward pressure between the thumb and index finger while gently pulling the clip away from the main plug.
Test drive.
Reverse process, utilizing thumb and index finger.![Big Grin](https://mbworld.org/forums/images/smilies/biggrin.gif)
Test drive.
Reverse process, utilizing thumb and index finger.
![Big Grin](https://mbworld.org/forums/images/smilies/biggrin.gif)
#25
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C32
04 c32.
about 40k.
Strange... when at a dead stop, and give pretty good acceleration (but nowhere near full throttle) the car takes off fine, but then right at about 2800 rpm the car thuds and trips the traction control light. It doesn't feel like the rear is breaking loose. It feels almost like the car is shifting into second, and the gear change is really hard. However, it is happening in first.. cause I tried just staying on it, and I was able to go higher in the rpm range without issue in first. Only happens when I push the car semi hard. Think of it as when you are in a two lane road that merges into one lane.. you want to be first, but don't need to go all out.
I did a search and many seem to have a similar experience at 1500 rpm being glycol contamination. Is this what I should be looking at as well? Any thoughts appreciated. Thanks.
about 40k.
Strange... when at a dead stop, and give pretty good acceleration (but nowhere near full throttle) the car takes off fine, but then right at about 2800 rpm the car thuds and trips the traction control light. It doesn't feel like the rear is breaking loose. It feels almost like the car is shifting into second, and the gear change is really hard. However, it is happening in first.. cause I tried just staying on it, and I was able to go higher in the rpm range without issue in first. Only happens when I push the car semi hard. Think of it as when you are in a two lane road that merges into one lane.. you want to be first, but don't need to go all out.
I did a search and many seem to have a similar experience at 1500 rpm being glycol contamination. Is this what I should be looking at as well? Any thoughts appreciated. Thanks.
Last week, I have the tranmission control unit reset and everything back to normal. You can try this first before glycol test