Back to 1998 Toyota 4Runner

1998 TOYOTA 4RUNNER

2.7L I44WDAUTOMATICgas
4 active safety recalls on this vehicle — view recalls
Repairs0Labor516Torque6148Fluid9DTC661Battery1Maintenance0Recalls4
P2001high severityPowertrain

NOx Trap Efficiency Below Threshold Bank 2

on 1998 Toyota 4Runner 2.7L I4 · 4WD

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

Building an app?
Free API access to all this data — 50 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →