P2002: Diesel particulate filter efficiency below threshold (bank 1)
The diesel particulate filter is not trapping soot as well as it should.
Updated
What P2002 means
A diesel particulate filter (DPF) catches soot from the exhaust. The engine computer judges it by the pressure difference across it, measured by a differential pressure sensor: a filter that holds soot builds up a pressure difference.
When the difference stays lower than a working filter should give, the computer concludes that soot is getting through, and stores P2002. It’s the opposite of P2463, a clogged filter.
Can I keep driving?
Check soon
Probably OK to drive short-term, but have it checked soon. Fuel use or emissions may be worse.
General guidance based on the code alone, not on the car’s actual condition. If in doubt, stop and ask a mechanic.
Soot getting through raises emissions. Inspections with a particle count, such as the Dutch APK for diesels with a particulate filter, measure exactly that.
Symptoms
- Often just the check engine light.
- On some cars, a particulate filter warning.
- Soot inside the tailpipe, which stays clean with a working filter on many cars.
Common causes
- Cracked or removed particulate filter. A crack lets soot pass. A filter that was removed or emptied sets this code too.
- Faulty differential pressure sensor or hoses. A split, disconnected or blocked hose to the sensor makes it read too little pressure difference. Check these first.
Typical fixes
- Check the pressure sensor’s hoses for splits, blockages and loose ends.
- Have the sensor’s reading checked: with the engine off, it should show close to no pressure difference.
- Have the filter inspected, and replaced if it’s cracked.
- Clear the code after the repair. Under emissions readiness, the PM filter self-test shows when the car has re-tested it, on cars that report it.
Questions
Can I drive with P2002?
Probably for a short time, but have it checked soon: the app’s advice is that fuel use or emissions may be worse.
Is P2002 the same as a clogged filter?
No, it’s the opposite. P2463 means the filter is clogged; P2002 means it lets soot through, or the sensor says so.