Vintage Valve Adjustment: Factory Secrets

Hello,

Shortly after I bought my Ibiza with approximately 23,000 km on the odometer, I noticed that the (airless) charging valve wasn't fully engaging the VTG lever, as if someone had shortened the rod.
As far as I can tell, the factory-applied protective coating was intact, and the LVD (Low Voltage Directives) compliance also showed only relatively small overshoots, which is typical for VTG (Vertical Traveling Grip) rods with shorter stroke lengths.
The MSG software was genuine.

Therefore, I assume that the turbocharger (a GT1749VB) was already adjusted from the factory in such a way that a portion of the possible variable turbine geometry (VTG) range (in the open area) is intentionally sacrificed.

Does anyone know why this might be the case? Is it a specific feature of the Cupra vehicle battery charger?
In all other VAG-VTG turbochargers that I have previously worked on, the can presses the VTG lever against the open stop of the mechanism with slight force .

Hello Ulf,

Foreign objects (dirt) may have entered the can through the opening in the rod.

Best regards, Rainer.

Rainer K. wrote:

Foreign objects (dirt) may have entered the can through the opening of the rod.

Hi Rainer,

Of course, I can't completely rule that out.
However, the VTG (Variable Turbine Geometry) passes the spray test flawlessly, meaning that any potential debris no longer causes blockages, but instead slips between the vane and its opening.
For this, the size of the crumbs must be very tiny, and the fact that such fine dirt in the container can reduce the travel distance by approximately one thread pitch, while simultaneously replicating the hard stop of an intact can without any creaking or the like, seems (so far) practically unthinkable .

My question from a while ago: VTG at Pmax with the valve fully open?
/viewtopic.php?t=22024
It gains a facet that I didn't expect.

Best regards, Klaus.