P2002 – Diesel Particulate Filter Efficiency Below Threshold – Opel 1.6 / 1.7 / 2.0 CDTI (Opel / Vauxhall 2.0 CDTI (A20DTH, A20DTJ, A20DTE) – Insignia A, Astra J, Zafira C, Cascada)

Fault code P2002 means "Diesel Particulate Filter Efficiency Below Threshold – Opel 1.6 / 1.7 / 2.0 CDTI". It is common on 2.0 CDTI (A20DTH, A20DTJ, A20DTE) – Insignia A, Astra J, Zafira C, Cascada, 1.7 CDTI (A17DTR, A17DTS) – Astra J, Meriva B, 1.6 CDTI (B16DTH, B16DTL) – Astra K, Insignia B, Zafira C, Mokka A engines. Below are the real-world causes, step-by-step tests and OEM part numbers.

Last updated 19 October 2026

P2002 quick summary

Fault code	P2002
Meaning	Diesel Particulate Filter Efficiency Below Threshold – Opel 1.6 / 1.7 / 2.0 CDTI
System	Powertrain (Engine & Transmission)
Vehicles	Opel / Vauxhall
Common on	2.0 CDTI (A20DTH, A20DTJ, A20DTE) – Insignia A, Astra J, Zafira C, Cascada, 1.7 CDTI (A17DTR, A17DTS) – Astra J, Meriva B, 1.6 CDTI (B16DTH, B16DTL) – Astra K, Insignia B, Zafira C, Mokka A
Severity	Medium
Can I drive?	Yes, but have it checked soon. Often the fault is a sensor or hose, but a cracked filter or a blocked one (P2463) needs attention before the engine goes into limp mode.
Repair cost	€40 – €2,500

Symptoms of P2002

Check Engine light, sometimes the DPF warning light
Regenerations not running or running very often
Engine oil level rising (fuel dilution from failed regenerations)
Loss of power or limp mode if the filter is really blocked
Soot in the tailpipe (cracked filter)

Most common causes of P2002 (most likely first)

Mechanic's Pro Tip

On Opel CDTI engines P2002 is very often caused by the DPF differential pressure sensor or its two hoses, not by the filter. Compare the pressure value with the engine off (should be about 0 mbar) and at 2,500–3,000 rpm. Also check the oil level: if it is above the max mark and smells of diesel, regenerations have been aborted repeatedly – change the oil before forcing a service regeneration, otherwise the diluted oil can damage the turbo and bearings.

1.Faulty DPF differential pressure sensor
Most likely
2.Cracked, blocked or swapped sensor hoses
3.DPF cracked or melted after an uncontrolled regeneration
4.Filter full of ash at high mileage
5.Frequent short trips that never let a regeneration finish

Step-by-step diagnostic guide

1
Read all codes with OP-COM, MDI or a GM-capable scanner and note soot load, ash load and differential pressure.
2
Check the pressure value with the engine off and at about 2,500–3,000 rpm; a value stuck near zero points to the sensor or hoses.
3
Inspect both sensor hoses for cracks, kinks, condensation blockage and correct connection (upstream/downstream).
4
Check the engine oil level and smell for fuel dilution; change the oil if it is diluted.
5
Replace the sensor or hoses if faulty, then run a service regeneration; only replace or clean the DPF if the filter itself is confirmed faulty.

Frequently asked questions

Does P2002 mean my Opel's DPF is blocked?

Not usually. P2002 means the control unit thinks the filter is filtering too little. A blocked filter more often sets P2463 (soot accumulation). On CDTI engines the differential pressure sensor and its hoses are the most common cause of P2002.

Why is the oil level rising on my Insignia 2.0 CDTI?

During regeneration extra fuel is injected late, and part of it ends up in the oil. If regenerations are interrupted by short trips, the oil level rises. Change the oil with the correct low-ash specification and allow longer drives so regenerations can finish.

How much does it cost to fix P2002 on an Opel CDTI?

A differential pressure sensor costs about 40–120 € and hoses a few euros. Professional DPF cleaning costs about 250–500 €; a new filter (often combined with the oxidation catalyst) about 800–2,000 € plus labour.

Related fault codes

This guide is for information only. Working on vehicles can be dangerous — if you are unsure, have the car checked by a qualified mechanic. Values can differ between model years; always check the manufacturer's repair information.