Crankcase Ventilation vs. Turbocharger Control

Hello everyone and Merry Christmas!!

During the "inspection" of my boost pressure control system, I noticed a hose that ends abruptly in the spray bar without connecting to anything. Additionally, the central connector on the boost pressure control solenoid valve is not connected.
According to the schematic overview "Charge pressure and exhaust gas control" in SSP 145, this connection should also not be occupied. However, after obtaining the test instructions for my engine from Erwin (siehe Fehlerdatenbank) yesterday, I see in the wiring diagram that the catalytic converter (KGE) is connected to this solenoid valve.

Could someone explain the context here? Did my predecessor perhaps intentionally disconnect this hose, and what effects might they have hoped to achieve by doing so?

Thomas.

Hi,
I suspect that the mentioned connection for the solenoid valve is only connected to the compressed air system so that the valve is not exposed to any contaminants, but only receives clean air.

Deleted upon request.

Hello,

I have now connected the N75 vent connection as described in the Erwin (siehe Fehlerdatenbank) documentation. Subjectively , there is no noticeable difference. However, I will perform a logging session at some point and then record the boost pressure and air mass, comparing them with previous recordings.

I also checked the N75: the resistance is 24 ohms, and the applied voltage is just under 12 volts, which is the battery voltage, so both values are within the tolerance ranges. However, could the component still be faulty in a way that is not apparent from these measurements?

CU
Thomas.

Deleted upon request.

Hello diesel.gustav,

With my inquiry, it was important to me not to make any mistakes! I was just a little confused because in SSP 145, the ventilation connection at N75 is not connected to anything (I had noticed this before), and in the repair manual, the same connection is connected to the crankcase ventilation system. Different representations, even though both sources officially come from Audi.

I am still looking for a cause for my strange boost build-up and have come across a potential leak in the pressure system. However, I think I may have found something: I'll provide more details later, after I've reviewed the issue more closely and can give more precise information, otherwise this will turn into another guessing game again...

Regards,
Thomas.

Deleted upon request.