No Boost? V6 Naildown Fixed Above 2200 RPM

Hi.
I'm having a problem with a 2.5 V6 TDI engine, model BAU, with 281,000 km on the clock.
The engine is not building any boost pressure, or a minimal amount, up to a maximum of 0.1 bar.
The air mass flow rate is 400 mg/H at idle, and approximately 430-450 mg/H at full throttle.
In addition, the fuel injection timing shifts from 6° BTDC (Before Top Dead Center) to 2° ATDC (After Top Dead Center) at approximately 2200 RPM.
What was done?
Intake side is clear. Exhaust side is also clear.
The VTG pole moves back and forth during the load test without any noticeable jerking.
"Spritzbeginn" also translates to "start of injection molding" or "injection molding start". So, a possible translation is:

"The start of injection molding is also suitable."

Or, more simply:

"Injection molding start is a good fit."

Or, depending on the context:

"The injection molding start time is appropriate."
I haven't checked the AGR yet.
I was already thinking that the VTG (variable geometry turbine) might be defective in the turbocharger.
I'm a bit lost right now and need your help.
Best regards,
Dirk

Hello,

Quote:

The VTG pole moves back and forth during the load test, even without any jerking

.
gestet mit der VCDS Stellglieddiagnose? Or with a syringe?

Regarding the sudden, erratic start-up: Is there a similar issue with the BAU engine, possibly due to software errors?
/viewtopic.php?t=25067&start=24

Best regards, Rainer.

Hi.
Performed using VCDS actuator diagnosis.
I need to observe the start of the spraying process again.
Best regards,
Dirk

Is it knocking? Does the engine also smoke? When did the problem occur? And not randomly after a certain period of full load?

Try disconnecting the intake hose from the turbocharger and check if the turbine shaft is intact and can rotate freely.

Best regards, Rainer.

Hi.
Problem solved.
I've taken a good look at everything again.
I tested the loading mechanism again, and this time the rod doesn't move. I don't understand why it might have moved last time, but sometimes things just happen that way when you're in a hurry.
Then check if the vacuum reaches the turbocharger, and of course, there's nothing there. There's nothing at the control valve either, nowhere except directly at the connection to the pressure control valve.
After some investigation, it was found that the boost pressure control valve always had a connection between the vacuum side and the atmosphere, which explained why the air mass was high at idle.
Best regards,
Dirk