Also check this for EGR error
Check wiring between test box and connector for open circuit using current flow diagram.
Contact 1+ socket 1 + 2
Contact 2+ socket 61
Wire resistance: max. 1.5 ω
Additionally check wires for short to one another, to vehicle earth and to battery positive. Specification: ∞ω
For this check (and the following) you must have access to the ECU socket. Remove the cover marked with the red arrow and then pull the plug by pulling in the direction of the arrows
EGR can be visually checked if it works: when you accelerate strongly you can see how the rod moves
With the blue arrow I marked the flap on the intake that is not related to the error on the EGR, but works with it and may be to blame for the lack of power.
Remove the inlet pipe and observe the flap:
engine stopped: the flap must be wide open
engine start/idle: the flap must be closed and after about 10 minutes idling without touching the acceleration will open ( to close again you have to drive at higher speeds )
engine accelerated at over 3000 rpm: the flap must be wide open
This is the correct behavior of this flap