Starke Vibrationen beim Beschleunigen (Solution) | Posts 16+

DieselBär30x wrote:

At a water depth of 15 cm, it should also be possible to rule out the presence of water in the cooling system.

Hi DBear,

You're forgetting about the car's front bumper!

If the bow/axis of the vehicle is not completely above the water, the car pushes the water in front of it, causing it to pile up. Depending on the speed and the shape of the vehicle's front (a wedge-shaped design that slopes outwards allows more water to flow sideways instead of piling up; a wedge-shaped design that points upwards causes the water to rise quickly).

It doesn't take much speed to cause water to flow over the hood when the bumper is submerged at a depth of only 5-10 cm (which means a total water depth of 20-25 cm). This is especially true because the vehicle experiences significant deceleration upon entering the water, which causes it to sink even further.

Greetings.
Guste, who, during his younger years in Florida, once ruined an engine due to a hurricane...

Okay, so the drive shaft is now installed and it's improved a little, but the vibration/shaking is still there.
I've logged the MWB 13 18 23 values again with the engine running at its normal operating temperature.


I suspect the right side of the driveshaft because I just noticed that it also has a tear in the inner boot.
But somehow, I can't believe that both joints would fail at the same time.
What do you think?

Okay, so I've done a few rounds and noticed that the vibration is sometimes there and sometimes not.
I also created two log files just now.
Unfortunately, the vibrations were very minimal during both trips.
Maybe someone will learn something from this.
I'm really starting to feel desperate.

Quote:

But somehow, I can't believe that both joints would fail at the same time...

I don't either - maybe you just replaced the ones with fewer defects...

Unfortunately, without a detailed description of the problem, it's difficult to provide truly helpful and reliable assistance.
You'll need to figure out yourself when, where, and how the shaking occurs – whether it's more pronounced when driving straight or while turning, etc. – and then let us know. Try to pinpoint the issue through test drives.

Okay.
So, it vibrates the most when under load. When driving uphill, this is extremely noticeable, starting around 1500 RPM and continuing until the engine reaches its maximum speed.
While driving through curves, there's hardly any change. I drove around a roundabout here, really letting the waves on either side carry me along. -> Hardly any difference.

"Now, I'm starting to feel a slight throbbing or vibration even when I release the accelerator and let the car coast."
I'm going to order the next drive shaft right away .
What do the logs look like? Can we rule out the engine as a source of the problem?

Thank you for your help.
Best regards, Thomas.

Quote:

Can the engine be ruled out as a source of the problem?

Based on the idle speed control, I would actually say yes. The fact that the vibrations don't occur constantly also argues against bent connecting rods, etc. However, you can never be 100% sure. For example, if a connecting rod bearing is damaged and partially rotates, it might have play sometimes and not at other times... Only time will tell.

It's possible that the error is occurring now by chance. Is the diesel filter okay?

The diesel filter is approximately 8 months old.
"This valve on the filter might be leaking... I've experienced that before, but it caused completely different symptoms then."

Has it been happening since the ZMS was removed?
Could you please repeat that log with the same parameters? Warm engine idling, and include 2 or 3 quick throttle blips.

No, I've only been experiencing the vibrations for a week.
The ZMS has already been installed with 9,000 kilometers on the odometer.
I will try to create another log while the system is in a warm state.
Unfortunately, it's no longer possible to drive it. The vibrations are too strong.

Hi there,
"While it's not entirely impossible that the motor or drive shafts are the issue, much points towards the dual-mass flywheel (DMF). The vibrations are increasing under load and over time. Furthermore, the DMF was only recently installed (how and where?)."
With increasing damage to the engine, noises should also occur. Damage to the drive shafts typically results in noises during changes in load.
Is the engine/transmission mounting okay?
hg
Herbert.

Derzeit ist ja das VALEO 4K Kit drin. So, an EMS.
The motor mount appears to be okay.
The transmission mounting was also replaced during the installation of the dual-mass flywheel.

Now the second drive shaft is installed, and the problem is still there... it's significantly better, but not completely gone.
Please find the requested log file attached.

Anyone else have any ideas?
How can you precisely detect damage to the engine bearings?
If I leave the hood open and release the clutch in first gear with the handbrake engaged, I can't detect any significant angular movements or noises.

Kitwing wrote:

Anyone else have any ideas?? How exactly can you detect damage to the engine bearings?

In my car (AVF), both engine mounts leaked fluid back then, which was also clearly visible at the bottom of the two drain pipes.
The hydraulic suspension on the left side (driver's side) is electronically controlled and should be diagnosable through the engine control unit, but it didn't register any error codes. However, the phone and the garage door opener – which were located in the center console – started to malfunction under load, starting around 1600 RPM. Since the replacement, everything has been working fine.

However, your problem will likely continue to plague you for quite some time until you manage to reduce the torque.
Within my circle of acquaintances, I have already witnessed something similar with a Golf 4 equipped with an ASZ engine and a "Superchip" .
According to the specifications, it had 420 Nm of torque and 180 horsepower. After 2000 km, the clutch failed, followed by a faulty dual-mass flywheel (DMF) after another 3000 km. It also experienced severe idling problems, which led to an engine management system (EMS) replacement, but the issues persisted. Ultimately, the vibrations caused damage to the transmission.
Now it has a new clutch and flywheel, along with modified software (380 Nm of torque sustained for longer), and the vibrations were already gone after the software change.
I'd try it myself first, before you waste even more money by randomly experimenting.


Regards,
Mpire

Thanks for the tip. I actually had the torque reduced last week as well.
The tip about the engine mount is helpful.
I noticed a thin oil leak near the bearing on the passenger side.
I'll be replacing this one too. However, I'm wondering how to loosen the top screw, as the turbo is directly on top of it.
I just don't want to hope that the transmission is broken.

There's some news:
I took the car to a friend's workshop yesterday.
Current diagnosis:
- Slight defect in the engine mount on the passenger side.
- Gearbox mounting defective, passenger side.

He can repair both of them. What surprised me is that he can replace the bearings on the transmission... I'm curious to see how it turns out. He should be finished by Friday. I will keep you updated.

He's referring to "lager" as in hydraulic bearings or rubber-metal bearings. Why shouldn't he be able to replace them?
hg
Herbert.