DPF values, engine control lamps (Rosselklappe)

Hello, with my P. the motoro control light has been shining for some time. Now I have read out the error memory by means of VCDS. The following error is filed: 005445 – throttle control; P1545-002 malfunction. I suspect that the throttle valve is rusty, or there is another mechanical error. Where exactly is the throttle valve with the 3.0 V6 TDI? What is the cost of a new throttle valve? Furthermore, this error probably prevents the regeneration of the DPF, because mine was recently burned free before 980km. I have read the following values by means of VCDS: Oil ash volume: 0.32 Load ash mass value calculated: 40,2 Load ash mass value measured: 1.2 Distance since last regeneration: 980km How about my particle filter? How long can I drive before the filter clogs? Up to what maximum value can I still burn the particle filter free?