P2001 OBD-II: nox Adsorber Efficiency Below Threshold

P2001 Severity

Moderate

Will P2001 go away on its own?

Once the vehicle's onboard system no longer detects the issue, most codes will disappear on their own. If your vehicle still has this code, however, it should be properly diagnosed to avoid a more serious problem.

For a proper diagnosis, RepairPal Certified shops have the equipment, tools, and expertise.

Moderate severity codes might not threaten the vehicle's safety or functionality immediately, but you should still get it diagnosed within a reasonable time frame to keep your car running well.

Schedule Diagnosis

What causes OBD-II fault code P2001?

Diesel Exhaust Fluid (DEF) is used to assist in converting leftover exhaust particles to harmless gases. In order to burn off those particles, the temperature of the exhaust system needs to increase. the injection of DEF Fluid into the exhaust stream brings Diesel Particulate Filter (DPF) up to temperature. The system is then able to convert harmful NOx to Nitrogen, Carbon Dioxide, and water. The Reductant Catalyst (SRC) was added to further reduce any NOx was still in the exhaust stream. If the DPF cannot sufficiently burn off all the particles, code P2001 is set.

Need a P2001 diagnosis? Trust our experts.

RepairPal Certified shops provide expert diagnostics and repairs with transparent upfront pricing and a minimum 12-month or 12,000-mile warranty on all services.

What Does P2001 Code Mean?

OBD-II Code P2001 is defined as a nox Adsorber Efficiency Below Threshold

Diesel Exhaust Fluid (DEF) is used to assist in converting leftover exhaust particles to harmless gases. In order to burn off those particles, the temperature of the exhaust system needs to increase. the injection of DEF Fluid into the exhaust stream brings Diesel Particulate Filter (DPF) up to temperature. The system is then able to convert harmful NOx to Nitrogen, Carbon Dioxide, and water. The Reductant Catalyst (SRC) was added to further reduce any NOx was still in the exhaust stream. If the DPF cannot sufficiently burn off all the particles, code P2001 is set.

Common Problems That Trigger the P2001 Code

  • Diesel Particulate Filter (DPF) failure
  • Intake air leak
  • Mass Airflow (MAF) sensor is dirty/loss of calibration

Common Repairs Needed for the P2001 Code

RepairPal Car Genius

Ask our experts about P2001.

RepairPal Car Genius™ is a free resource for vehicle owners seeking advice on maintenance, auto repair, shop inquiries, estimates, and finding a trustworthy repair shop in your area.

 Auto Repair Expert Auto Repair Expert

Call us at 877-913-1554

Available 9am – 6pm ET Monday through Friday

Call Our Experts