Turbo Shovel Noises: Adjustable Sounds Possible?

My TDI-PD ATD Octavia has been making strange noises when accelerating, mostly in 1st-3rd gear, since around 20,000 km. I now have 64,000 km on it.
Ich hatte das bei jedem Werkstattbesuch bemängelt aber scheinbar interessiert es keinen oder die haben Stöpsel in den Ohren. Bis vor Kurzem trat dies nur beim Beschleunigen aus dem Stand auf, kommt aber seit ca 4 Wochen auch, wenn ich zuvor abgebremst habe. Gestern und heute habe ich mal den Drehzahlmesser beobachtet, das tritt immer zwischen 1500 bis 2000 Umin auf. Seltsamerweise sind diese Geräusche nicht bei allen Beschleunigungen zu hören, sondern treten nur bei mittlerem bis leicht stärkerem Beschl. auf; also bei schwacher oder starker nicht. Der Rhythmus dieses Geräusches wird leicht schneller mit zunehmender Drehzahl aber nicht proportional. Die Intensität des Geräusch hängt von dem Maß der Beschleunigung ab aber nicht der Rhythmus. Oft ist dabei auch im gleichen Rhythmus wie das Geräusch eine pumpende Beschleunigung zu spüren (Das Fahrzeug tut leicht reiten). Das Geräusch kommt so aus der Gegend des Tunnels des vorderen Fußraumes. Habe mich schon gefragt, ob es an einer rhytmischen Verstellung der Außenschaufeln des Turbo liegen kann, also vom Auf- und Abregeln des Ladedrucks; also daß es ein Bereich ist, wo er nicht so richtig einen konstanten Druck einstellen kann. Die Klangfarbe des Geräusch erinnert mich so eher an ein Getriebe mit kleinen Zähnen, das man hin und her dreht. FI'm just wondering if you can actually hear the sound of the gearbox from the blade adjustment mechanism inside the vehicle.

Does anyone have any advice or suggestions on what might be causing this?

Otherwise, the engine's performance shows no particular anomalies, except that I believe the power occasionally drops noticeably at altitudes as low as 300 meters. For example, on the highway, when climbing (at a 7% gradient), I sometimes have to ease off the accelerator because of slower vehicles. When I then accelerate again, I occasionally feel like the power is gone, and even downshifting doesn't seem to help. This is independent of whether new filters have been installed or not. The mass airflow sensor (MAF) is supposedly okay.


Regards,

Irish beer.

Is this something that might interest you?
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m;

Hello,

The description of the noise phenomenon reminds me strongly of the problem I'm experiencing.
A squealing or hissing noise occurs during slight acceleration, below 2000 RPM.
I also suspect that the VTG installation is the cause, especially if I see something unusual with the VTG hose.
As soon as you disconnect it, the noise disappears completely (unfortunately, so does the power...).

The VTG adjustment is easy to adjust, but unfortunately, I haven't been able to make any further progress, as I don't have a diagnostic tool.

TDI-PD AVF engine with Tiptronic transmission, 160,000 km, turbocharger replaced.

Best regards,
Bernhard.

I had the same problem with my brand new Octavia.
While accelerating in 2nd, 3rd, and 4th gear, between approximately 1500-1800 RPM, there's a 'scraping-scraping-scraping' sound, accompanied by a noticeable drop in engine power, which results in a slight stuttering of the engine.

After the workshop initially tried to dismiss my concerns by saying, 'Skoda says this is normal behavior when driving at low RPMs,' I more firmly asserted my rights under the manufacturer's warranty.
Now the entire turbocharger has been replaced - and lo and behold: the jerking and rattling noises have disappeared.
The expert believed that manufacturing tolerances in the intake channels of the turbocharger were causing rhythmic pressure fluctuations. So, it wasn't a variable geometry turbo (VTG) problem, but rather something more like a vibrating air column.

dieselator wrote:

Now the entire turbocharger has been replaced - and lo and behold: the jerking and rattling noise have disappeared.

...and your old loader will probably be sold soon through eBay...

Probably, slightly extending the VTG rod would have been enough.