DFP differential pressure sensor
If you get trouble code: 5162 - Diesel Particle Filter; Differential Pressure sensor - P2453 00  - Implausible signal
(also 12307 - Particular Trap Bank 1 - P2002 00  - Efficiency Below Treshold occurs, but DFP Computational and measured degree of fulfillment was very low)
Replacemen part is that Differentian Pressure Sensor: 059906051A
Original Bosch replacement part ~ 42€ and OEM about 150€.
No doubt what I choose.
Easy to change. Located near by air in feed pipe back on engine compartment. I removed air in feed pipe to add more space to chance sensor.
There is only two pipe clamps that are tricky to change without proper VAG clamp pliers. But no any crews only plastig fastener.
Othet pipe goes to DFP and other is only about 10cm pipe to free air that let rounding atmosphere air pressure to sensor.