P2002

Particulate Filter Efficiency Below Threshold Bank 1

Diesel emissions / DPF Generic OBD-II Medium

What it means

P2002 means the diesel particulate filter (DPF) on bank 1 isn't trapping soot as effectively as it should. The engine watches filter efficiency — often through exhaust pressure sensors — and a low reading points to a worn-out, cracked, or poorly regenerating filter, or a pressure sensor reading it wrong. It usually shows up as reduced power and frequent regenerations.

Medium

Can I keep driving? Usually drivable, though you may notice reduced power or forced regeneration; long-term neglect clogs the filter and can require an expensive replacement.

Real-world scan data

Seen in

1,273

scans in the past year

Found in

0.2%

of scans

0.4%

of scans that found faults

Appears alongside · share of P2002 scans

P2263in 17.4% of scans

P0380in 16.9% of scans

P2080in 12.1% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Reduced engine power or limp mode
Frequent or incomplete regeneration cycles
Increased exhaust smoke or a sulphur/burning smell

Common causes

Most likely first

Worn, cracked, or damaged diesel particulate filter (DPF)Likely
Lots of short, low-speed trips that prevent proper regenerationCommon
Faulty DPF differential-pressure sensor or clogged sensor linesCommon
Air or exhaust leak upstream of the filterLess often
Poor-quality or high-sulphur fuelLess often
Faulty ECU (rare)Less often

How to diagnose & fix

Work through it in order

Scan freeze-frame and check for accompanying DPF pressure-sensor or regeneration codes.
Inspect the DPF and exhaust for leaks, cracks, or physical damage.
Test the DPF differential-pressure sensor and its hoses.
If the filter is loaded but serviceable, run a forced regeneration or take an extended highway drive.
Replace or professionally clean the DPF if it's beyond regeneration; clear and re-test.

FAQ

Quick answers

Is it safe to drive with P2002?+

Short-term, usually yes, but the car may lose power or force regeneration cycles. Ignoring it lets soot build up until the filter needs replacing.

Can I just clear P2002?+

Clearing it won't restore a clogged or damaged filter — the code returns once the DPF's efficiency is measured again. Address the filter or sensor cause.

Read & clear P2002 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX