Chiptuning: Vibrations Issues?

Hi,
I had my car tuned today at ********, or rather, by one of their authorized dealers. Since then, I've been experiencing a problem: when accelerating from the 3rd gear onwards, the car vibrates and shakes significantly, and the whole car is trembling. This only happens between 1600 and 2200 RPM. I've already done some searching in this forum, but I haven't found anything quite matching my issue. My suspicion is the clutch. Could that be it? When the engine is cold and I accelerate, it's not as bad (I know you shouldn't stress a cold engine, and I usually don't, but I have to figure out the cause somehow), and it seems like the clutch might be slipping a bit if you pay attention to the tachometer. I drive a Seat Ibiza with the original 110 HP and engine code ASV, now with approximately 140 HP according to ********. The mileage is 80,000 km. I would appreciate any tips you might have. Perhaps a reinforced clutch or something similar?

Hello!

I have the same car as Rainer, and I also had chip tuning done by ********. Mine also vibrates. As far as I know, all TDIs with increased torque do this; my wife's Pumpe-Düse engine also exhibits this behavior. This is not a ********-specific issue.
******** states that the cause is that the engine is being pushed more forcefully into the engine mounts, and that vibrations, which are normally present, are now being transmitted more directly into the body. I've seen this happen before. When running at full throttle on the test stand, the entire engine block almost comes flying forward.
I don't really believe that theory about vibrations becoming noticeable in that way. I suspect it's more likely due to the two-mass flywheel, which somehow becomes unbalanced with that enormous torque (I'm not exactly sure how that happens), or, as Rainer already mentioned, the vibration damper in the clutch is completely compressed and can no longer dampen.
I've been using a chip for 130,000 kilometers and it helps to reduce vibrations somewhat. However, when I need more power, I still accelerate. I haven't experienced any problems that can be attributed to the chip.
Unfortunately, at higher ambient temperatures (summer), the torque of our TDI engines decreases, which also results in a slight reduction in vibrations. I have a more powerful chip to compensate for this. However, now in the winter, the vibrations are quite bothersome.
So, no need to panic, it seems the vibrations aren't doing any harm to the engines (hopefully...).

Best regards,
Uwe.

Rainer K. wrote:

My car (A3, engine code AHF) also does that, since a device was installed. This topic was discussed in this forum a long time ago, but, to my knowledge, a definitive cause was not identified. The clutch's vibration damping springs are suspected, as they may not be able to withstand the torque.

Hi everyone,

To complete the confusion:
An AFN engine with the large injectors from the 111 kW 5-cylinder engine, when equipped with an active tuning box, can reach around 150 horsepower (according to DZR).
Surprisingly, the shaking is largely absent, which was clearly noticeable and reliably reproducible with the standard nozzles and the same box settings.

I can't explain it, no matter how hard I try.

Hi,

It also surprised me. Mine doesn't shake like it's supposed to.
Not even when I was still driving that piece of junk from ********.

I think it's pretty clear that the engine mounts will eventually wear out.
But whether normal wear and tear at 80,000 km should be the cause of increased vibrations? Mine is about to reach 165,000 km, and the first bearings are already behind us...

Maybe it really is the nozzles.
When comparing, all newer VP-TDI engines have fuel injectors that open at 220 bar, while older VP-TDI engines, up to the AHF model, open at 190 bar.

I recall a thread where someone attributed vibrations and engine running issues to certain pressure settings. However, I'm not entirely sure about it myself.

Greetings.
Thomas.

@Ulf!

Vielleicht ist bei Deinem AFN die Drehmomentkurve flacher und hat nicht diesen Peak bei 2.000 U/min. Ich habe ganz bestimmt über 300 Nm! What do you mean?

Best regards,
Uwe.

Hello everyone,

I've also been driving one for quite some time, about 10,000 kilometers.
AFN 81 kW Passat.
And since that time, I've had a chip (tuning box) installed.

These vibrations do not occur for me.
The only problem I have is that when you...
The engine is revving too high due to the tuning box.
It switches to emergency mode due to excessive boost pressure.
So much energy is released here that it affects the control system.
The vacuum sensor from the VTG (Verband Verkehrstechnik) is not sufficient to maintain the required boost pressure.
to reduce.

Regards,
hturbo01

Hi,

Quote:

... because the engine is being revved up too much by the tuning box. It switches to emergency mode due to excessive boost pressure.

The engine power is not actually increased by a tuning box.
This only changes the injection times.

Quote:

Vielleicht ist bei Deinem AFN die Drehmomentkurve flacher und hat nicht diesen Peak bei 2.000 U/min. Ich habe ganz bestimmt über 300 Nm! What do you mean?

"Mine, according to ********, produced 370 Nm of torque at 2100 RPM, and there were no particularly noticeable vibrations. But by the way, these measurements aren't really very informative!"

Greetings.
Thomas.

Thomas wrote:

Mine, according to ********, had 370 Nm of torque at 2100 RPM, and there were no particularly noticeable vibrations. But by the way, these measurements are not really meaningful!

"Um, are you perhaps referring to 270 Nm? The 110 model comes standard with 235 Nm, and with 300 Nm, it's already a significant increase in power. Or are you referring to a different model than the one mentioned below?"

Best regards,
Uwe.

Hi,

No, no, that's actually correct! The dyno test results are also floating around somewhere in this forum.

But seriously. According to the dynamometer test, it produced 370 Nm, but is that really accurate?

Greetings.
Thomas.

Wrong way.

Could you create a "Ulfschen Durchzugsrechner"? (This is a very specific request and likely refers to a particular type of calculation or tool.)

Best regards,
Uwe

Hi,

Correct approach. But why is that important if you already know the translations?

@Uwe

Unfortunately, the DZR only reproduces the torque curve typical of TDI engines, not the actual one.
resulting in a torque value of only approximately 350 Nm.

In reality, that might not be entirely accurate, but there must be something that causes the clutches to slip!

... but now we're quite off-topic!

Greetings.
Thomas.

Good evening.

The vibration comes from the crankshaft mechanism, specifically the crankshaft itself. If you exceed the boost pressure, it can cause vibrations, especially at certain critical engine speeds, typically around the maximum torque.
The dual-mass flywheel can no longer compensate for this, and the vibrations are transmitted to the body, making them noticeable. This is also a problem with the vibration dampers on the timing belt side, as they can come loose!

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.

Hi,

It's possible, you're talking about the knocking sounds that can be caused by higher LD (lambda value) or premature injection. But in that case, I think the vibrations would probably be the least of the problems. It could lead to engine damage, such as the turbo failing, the pistons melting, or just the head gasket blowing. I once temporarily increased the boost pressure to about 1.8 bar using a check valve from pneumatics, and it didn't cause any vibrations at all.

"Mine also never had a dual-mass flywheel, so it can't compensate for anything related to that. Therefore, that can be ruled out as a cause. Determining vibrations in the crankshaft is also likely to be somewhat time-consuming at the moment. Perhaps the best approach is to accelerate smoothly and sensitively within that specific RPM range."

Keep in mind that not all vibrations are the same.

Greetings.
Thomas.

hahahahaha - here we go again with the ZMS issues.

Does the AFN now have one or not? Are we talking about the newer AFNs, or what exactly?

I once looked into it because I used a flywheel from a G60 in my Corrado TDI, and I had been searching for one for a long time. Eventually, I bought a new one (6XX Euros) and installed it. It was a dual-mass flywheel, as stated in the ETK_A.

ZMS or not ZMS, that is the question . Everyone says something different - I don't even think VW itself knows what's going on.

Regards,
arne

Hi Arne,

I remember that thread. Anyway, my AFN model, manufactured in '97, doesn't have a dual-mass flywheel.
Perhaps someone can convince Ulf to remove his gearbox.
Then, at the very least, we could draw conclusions about the '97 AFN engines used in the Golf 3.

But don't ask me where and when these things were installed, and I also can't imagine that it has anything to do with the vibrations.

Greetings.
Thomas.