Defective Dual Mass Flywheel: Symptoms & Repair

Hello everyone,

I haven't found a solution yet, but maybe someone can help me based on the symptoms.

1) In the RPM range of 1000-1400, when accelerating gently, I experience a very dull, throbbing sound that is painful to the ears.
'In all gears, but especially in the second gear, I experience a very unstable engine running and vibrations in the vehicle when accelerating, specifically within the range of 1200-1600 RPM. It feels like the car body is shaking horizontally from side to side.'
'When I'm steering within the engine speed range of 1200-1600 RPM, I feel a pulsing in the steering wheel, as if I'm driving over small, short bumps. There's a kind of shuddering or vibration in the steering wheel.'
4) The engine noise is only a distinct 'grrr' like a diesel engine above 1900 rpm; at lower speeds, it's more of a very fast 'wupwup' sound (I admit, that sounds silly, but it's also hard to describe).
5) Measurement block 13, read with VAG-Com, shows the following values: -0.02 mg/H; -0.31 mg/H; 0.02 mg/H; 0.28 mg/H.

I hope you can help me. The workshop says that after reading measurement block 13, everything seems to be fine.
I am grateful for any input or ideas you may have.

Greetings.
Alex.

@everyone

Sorry, I forgot to include my vehicle details.
SEAT Alhambra 1.9 TDI (115 hp), 06/2004, 7000 km.

I am grateful for any advice that helps me with troubleshooting.

Regards,

Alex.

Okay, I can share my experiences from the weekend as a tip for you.
My car's clutch was slipping badly, so I replaced it this weekend (that was quite a job!).
Before the clutch replacement, I had a strong rumbling noise around 2500 RPM. After the clutch replacement, this noise is gone, and the engine is generally quieter. (The clutch also works great! )
I don't have a dual-mass flywheel, but the cause was likely the torsion springs in the clutch disc. I don't think the clutch itself was unbalanced.

I recently visited a different car dealership. The mechanic there said that this is common with the Alhambra, especially the diesel models, which tend to have problems with torque and the front axle because it's too weak. This explains the uneven engine running during acceleration and the vibration in the steering wheel.
Furthermore, the use of 16-inch tires would amplify the effects of the drivetrain on the steering.
The roaring sound is perfectly normal. The best thing to do is always drive above 1800 RPM; then it will disappear, according to his advice.
He said nothing at all about measurement block 13.

So, it's perfectly normal for an Alhambra.

I've also noticed something myself: When I accelerate quickly and then shift from first to second gear, I hear a rattling sound ('dradradadada') when releasing the clutch. The louder it gets, the more pronounced the noise is. It's quieter when shifting from second to third, and then it usually disappears altogether.
The exhaust doesn't make any contact with anything.

What do you think about it?

Best regards, Alex.