Vibrationen nach Chiptuning??? | Posts 16+

Hello Thomas,

Boost pressure doesn't equal power; I think everyone here knows that!
Do you actually know what forces are acting in the crankshaft mechanism? I can tell you it's tons! The vibrations overlap, leading to noticeable vibrations. This is the main reason why dual-mass flywheels (DMF) are used. The development was done by company LUK and is also patented by LUK. Audi was the first to start using them. Unfortunately, if you exaggerate the performance increase, the vibrations become so large that they can no longer be compensated for. The crankshaft deflects under load, and if you increase the combustion pressure, these undesirable resonances occur, believe me. The Japanese use balance shafts for this reason; Porsche unfortunately sold the patent to the Japanese back then! The reason isn't the DMF, but the performance increase!

Sure, here is the translation of the text from German to English:

'MFG' is an abbreviation for 'mit freundlichen Grüßen,' which means 'best regards' or 'sincerely.' It is commonly used in German-language emails and letters.

Thomas wrote:

Maybe someone can convince Ulf to remove his gearbox. Then, at the very least, one could draw conclusions about the ´97 AFN´ engines in the Golf 3.

Hi Thomas,

No, that's supposed to happen for the first time when the clutch needs to be replaced .

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but I also can't imagine that it's related to the vibrations.

I think (theoretically): after all, we have two moving masses (the crank mechanism with flywheel or the gearbox input to the wheels), and between them, there's a spring force, and that fundamentally always results in a system that can oscillate.
And it will oscillate once and for as long as the ongoing (in-phase) energy input is greater than the energy losses due to internal friction, etc.
(That's how I understand the basic function of damping in oscillating circuits, at least.)

Hi Ulf,

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nothing there, it's supposed to come off for the first time as scheduled, when the clutch needs to be replaced.

Sure!
It was just a joke. I mean, who would disassemble their transmission just to take a look at the flywheel?

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I think (theoretically): after all, we have 2 moving masses (the crankshaft with flywheel or the gearbox input to the wheels), and between them, there's a spring force, and that fundamentally always results in a system that can oscillate. (That's how I understand the basic function of damping in oscillating circuits, at least).

With the ZMS flywheel, there is vibration, even though this dual-mass flywheel is supposed to absorb vibrations. Conversely, with a rigid flywheel, there are no vibrations, even though it is supposed to promote a "rougher" engine running.
( That was my reasoning... )

You mean that the dual-mass flywheel is "overloaded" and can no longer compensate for anything because the operating range in which it can absorb vibrations has been exceeded? Did I understand that correctly?

If the dual-mass flywheel (DMF) is truly the source of the problem, then this phenomenon should occur in all or at least many performance-enhanced engines equipped with a DMF.

What about the idle speed control? Shouldn't that also come into play?

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And it will oscillate as long as the ongoing (in-phase) energy input is greater than the energy losses due to internal friction, etc.

Here, I don't quite understand the context. What kind of internal friction are you referring to?

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... The vibrations overlap, resulting in noticeable vibrations. [...] Unfortunately, if you exaggerate the power increase, the vibrations become so large that they can no longer be compensated for. The crankshaft deflects under load, and if you increase the combustion pressure, these undesirable resonances occur. [...] The reason is not the dual-mass flywheel (ZMS), but the power increase!

That may all be true, but why isn't mine vibrating? And I bet there are countless newer and more powerful TDI engines with dual-mass flywheels that don't vibrate either!

"So far, I haven't considered the ZMS (presumably referring to a vibration damping system) to be a necessity, but rather a kind of "comfort enhancement." I wouldn't rule out the possibility that I'm wrong, but I'm just bothered that there's absolutely no vibration in my Golf that could be caused by such a thing."

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Boost pressure is not the same as power; I think everyone here knows that!

Did I write that I wanted to increase performance by doing that?
If you're going to be disrespectful, please don't do it based on assumptions!

Greetings.
Thomas.

Hello Thomas,
I understood that you were driving with 1.8 bar of pressure to increase performance, what else would you do?
Perhaps you're lucky, and your engine is particularly well-made, your flywheel is well-balanced, or the other moving parts are well-matched.

Sure, here is the translation of the text from German to English:

'MFG' is an abbreviation for 'mit freundlichen Grüßen,' which means 'best regards' or 'sincerely.' It is commonly used in German-language emails and letters.

Thomas wrote:

I mean, who would disassemble their transmission just to take a look at the flywheel?

Hi Thomas,

For example, there are true enthusiasts who do nothing but cars in their free time and who also have access to a corresponding workshop... people like that exist .

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So, you mean that the dual-mass flywheel is simply "overloaded" and can no longer compensate because the operating range in which vibrations are absorbed has been exceeded? Have I understood that correctly?

Yes, basically, that's how I imagine it.

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If the dual-mass flywheel (DMF) is truly the source of the problem, then this phenomenon should occur in all or at least many performance-enhanced engines with a DMF.

It depends on the design of the ZMS (presumably referring to a dual-mass flywheel). As long as it can absorb more vibrational energy than the engine produces, it won't resonate.

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What about the running silence regulation? Shouldn't that also come into effect?

I'm not sure up to what RPM it engages or at what higher load it disengages (just a thought).

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And it will oscillate as long as and whenever the ongoing (in-phase) energy input is greater than the energy losses due to internal friction, etc. Quote: Here, I don't quite understand the context. What kind of internal friction are you referring to? Any oscillating system will eventually come to a stop without a constant supply of energy, because friction "destroys" the kinetic energy. This could be air resistance, friction in the bearings, or even "intentional resistance," such as in a shock absorber, to "dampen" any unwanted oscillations. That would take us too far afield...

Hi,

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For example, there are true enthusiasts who do nothing but cars in their free time and who also have access to a suitable workshop... there are people like that.

Hmm... I understand what you mean.
But no, we definitely don't belong there.

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It depends on the interpretation of the ZMS (Zweimassenschwungrad). As long as it can absorb more vibrational energy than the engine produces, it will not resonate.

That is to say, it's actually due to the tuning or the condition of the engine.
So, in a way, nadin_tu is right.

Running regulations:

In an idle state, this will definitely affect such inconsistencies.
Wouldn't it be conceivable that such vibrations could also be caused by a faulty...
LRR could arise? (Just a thought, ).

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Every oscillating system will eventually come to a stop without a constant supply of energy, because friction "destroys" the kinetic energy. This could be air resistance, friction in the bearings, or even "intentional resistance," like in a shock absorber, to "dampen" any unwanted oscillations.

Ok hab´s verstanden. Thank you!

@nadin-tu

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I understood that you were driving at 1.8 bar to increase performance, what else would be the reason!?

Because one morning, out of youthful recklessness, I moved to Koblenz to have my vehicle "tuned" with a different type of fuel injectors! The result was more of a failure than a success. There's a good story about that here in the forum. (Search: Erfahrungsbericht) In any case, I had a somewhat "fast" diesel vehicle since then. To see if soot emissions can be controlled with a bit more boost pressure, or whether more pressure alone results in less soot at higher RPMs, I temporarily increased the boost. Before I messed with the engine control unit (ECU) and started replacing any resistors, I wanted to know for sure. Ultimately, it does have something to do with more power, but those 1.8 bar specifically were not intended for increased power.
thought. I hope it reached you as intended.

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Maybe you're lucky, and your engine is particularly good, and your flywheel is well-balanced, or the other moving masses fit together well.

Maybe. I can't say for sure. The flywheel has a residual imbalance of 0.02g and weighs 3.5 kg itself. I don't know what that means. I don't know the standard values. Everything else is standard.

Greetings.
Thomas.

Hello Thomas,

You had your flywheel lightened and balanced, so everything should be sorted out. I believe a standard flywheel weighs more than double what yours does if you have a 228mm one! Ask where you had the flywheel balanced, or if the company also balances crankshafts. They can confirm what residual imbalance a newly manufactured crankshaft might still have. The manufacturers call this 'tolerance.'

Best regards,

Hi,

Why does everything always have to be so complicated?

To explain this to you, I have to go back a ways... well, never mind!

Since the standard clutch was too weak and literally failed at around 80,000 km, I took the Golf to an independent workshop and requested a stronger clutch. Without knowing what I was getting into, they installed a rigid sintered metal clutch with a reinforced pressure plate and a special flywheel. What was special about the flywheel was that it was bolted to the pressure plate multiple times on the outer edge.

Of course, a sintered metal clutch isn't practical for everyday use. After 30,000 kilometers, the friction material was completely worn out. When we then wanted to install a "normal" G60 clutch, the issue of the special flywheel came up again. It simply didn't fit. Since no VW dealer in the area had such a flywheel in stock, I quickly checked the largest online auction site, and luckily, a finely balanced and lightened G60 flywheel was being auctioned off that same evening. I bid on it for 100 euros and, upon receiving it, installed it immediately.

That's how I came to use the lighter, more finely balanced flywheel.

It's obvious that this whole thing is unbalanced. But now, to expand my KW specifically because of this... hmm, I don't know.

I once considered getting a roof rack installed, but since I need the car every day and it's not that easy to do, I think it's best to leave it.

If, for some reason, only the crankshaft were to break, which I can't imagine, and if a balanced one happens to be on hand, why not.

I once saw a TDI engine where all the components were meticulously balanced, and it ran incredibly smoothly. It was very interesting to observe.

By the way, I just checked. The original flywheel for the AFN engine weighs approximately 8 kilograms.

Greetings.
Thomas.

Okay, I understand the problem. So, if you ask me, cars only break down because of tinkering .

Sure, here is the translation of the text from German to English:

'Cu' is a Spanish word that means 'with'. It is often used in greetings, such as 'Hola, ¿cómo estás?' (Hello, how are you?). It can also be used to express agreement or support, such as 'Sí, cu'.

Here are some examples of how 'cu' is used in English:

* 'Hello, how are you?'
* 'Yes, cu'
* 'I agree with you'
* 'I support you'

I hope this helps!

Hi,

Your opinion was easy to read between the lines.

You're probably not entirely wrong. Fortunately, I haven't had any major problems so far.

However, it doesn't always have to be due to an increase in performance.

Greetings.
Thomas.

Hi,
Sorry, I haven't looked at my entry in a while, and it seems a lot of people have contributed. So, I probably won't think about it too much anymore; it's best to ease off the gas a little in that specific RPM range. After all, we can live with it. And since there are several people experiencing this phenomenon, and many have already driven a lot of miles with it, it probably isn't that serious.
Thank you very much again for your active participation.

Hello,

I drive a 1997 Passat 3B with an AFN engine.

Currently, the car has 200,000 km on the odometer, and he's been using a chip from 'INMOTION Tuning Austria' for the last 50,000 km.

Ich habe auch seit Anfang an dieses Ruckel-Problem im Drehzahlbereich um 2000 U/min beim Erreichen des max. Torque.

The tuning company informed me that this was a known issue and was normal (due to the high torque).

However, I had to replace the fuel injection pump at 195,000 km: The bearing for the ESP (Electronic Stability Program) wave was worn out. I can't say for sure whether this was caused by the chip tuning and the resulting jerking.

I'm still going to keep using the chip, and I'm going to ease off the accelerator a bit in that RPM range during acceleration... and then it works.

Hello, fellow victims of sudden jolts.

It's reassuring to know that this symptom seems to occur more often. I have the same issue with my Sharan 85 kW PD TDI AG 5, first registered in 01/01, and VW has been trying to fix it for a year. So far, everything has been replaced, including the AG with the control unit, except for the engine itself, but there has been no success.

Has anyone been able to solve this problem?

By the way, the car is still completely original, meaning it hasn't had any chip tuning.

Wishing you all a happy holiday season and a good start to the new year.

Best regards,

Peter.

'I'm experiencing the same issue. It started right after I installed my T4 injectors. There's a noticeable jerk at 2000 RPM, and then another one up to around 2400 RPM. It disappears if you ease off the throttle. I think it's the same phenomenon described here.'

Regards,
arne

'I had the same problem with my A4 1.9 TDI (130 hp). I had a tuning box from KW-Systems installed, and between 1500 and 2000 rpm, the car vibrated strongly in 3rd, 4th, and especially 5th gear. KW-Systems even reduced the power output below 2000 rpm, but it didn't help. The problem didn't occur when the engine was cold, or even during light acceleration, just like you're experiencing. I even went to Audi, but they didn't have a solution either, so I guess you just have to live with it.'
I've now got another KW-Systems tuning module in my A3 2.0 TDI, and thankfully it's working perfectly and completely vibration-free, it's awesome. If it had been faulty again, I would have returned it, but now it's just fantastic.

Best regards,