P2001high severityPowertrain

NOx Trap Efficiency Below Threshold Bank 2

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

The NOx storage catalytic converter on bank 2 is not efficiently reducing nitrogen oxides.

Symptoms

  • Check engine light
  • Failed emissions
  • Slight power loss

Common causes

  • Degraded NOx trap bank 2
  • Sulfur poisoning
  • Exhaust leak
  • NOx sensor fault

Diagnostic steps

  1. Check NOx sensor output bank 2
  2. Compare to bank 1
  3. Inspect exhaust for leaks

Repair notes

Replace NOx trap bank 2 if regeneration fails.

Other Powertrain codes on this vehicle

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