AKF Motor: Performance Issues & Troubleshooting (Solution)

3.3 liters, 8-cylinder TDI, AKF engine, up to serial number 4D 2N 001 542.
Lack of power, sudden power loss, the vehicle occasionally has no power, error code 17964 (boost pressure control limit exceeded).

Cause:
It is possible for the vacuum lines to tear, especially the angled connectors for the magnetic valves of the turbocharger pressure control system. Depending on the location and position of the lines, leaks and error messages may occur sporadically.

Procedure:
For error code 17964 (boost pressure control, lower limit exceeded), check for any leaks in the vacuum hoses. Pay particular attention to the angled connectors in the vacuum hose system. A vacuum pump can be used to apply vacuum to the hoses and check for leaks.

Sure, here is the translation of the text from German to English:

"Note: "
If error code 17567 (Signal from mass airflow sensor 1/mass airflow sensor 2: implausible ratio) is also stored in the fault memory, this is a consequential error related to a vacuum leak in the charge pressure control system. The mass airflow sensor should not be replaced in this case!