P047100 & P200200 on Polo 1.4 TDI (CUTA) – very frequent DPF regeneration

[electroasd]

Hello,

I have a Polo 1.4 TDI CUTA (2016, ~217K km) and I keep getting the following:
• P047100 – Exhaust Pressure Sensor “A” Range/Performance
• P200200 – Particulate Trap Efficiency Below Threshold

Problem:
• DPF regenerates every 15–30 km.
• I cleaned the DPF, replaced both Denso 04L 906 051 sensors, and did ODIS adaptation/reset (not sure what happened in ODIS this is what my mechanic said).
• Still the same: when measured soot mass reaches ~24 g → regen starts, drops to ~5 g → regen stops.
• After regen, soot mass sometimes keeps dropping into negative values.

Live data observations:
• Exhaust Pressure Sensor – Offset value ≈ -150 mbar (almost constant)
• Exhaust Pressure Sensor – Adapted value fluctuating between 0 and 50–60 mbar (based on rpm)
• Measured soot mass rises very fast (5 g → 24 g in ~20 km)
• Calculated soot mass rises slowly and only “jumps” to 24 g when regen starts

Has anyone else faced this exact situation?
What was the real fix in your case?

Thanks

[iichel]

did you check the hoses between the dpf and the sensors for any leaks?

[electroasd]

We only checked (couple of times) the small rubber hose going into the sensor, not the full metal pipe from the DPF. Do you think the metal pipe could be partially blocked with soot or leaking near the DPF connection? Could that explain the constant negative offset (~ -150 mbar) and the fast soot mass increase?

[iichel]

sounds like a broken sensor to me but since you already replaced that, i'd check anything else.