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2003 TOYOTA 4RUNNER
4.0L V6•RWD•AUTOMATIC•gas•1GR-FE
3 active safety recalls on this vehicle — view recalls
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Repairs0Labor489Torque1411Fluid8DTC1741Battery1Maintenance0Recalls3
P1133moderate severityPowertrain

Air/Fuel Sensor Circuit Response Bank 1 Sensor 1

on 2003 Toyota 4Runner 4.0L V6 · RWD

What this code means

The A/F sensor Bank 1 Sensor 1 is responding too slowly to exhaust changes.

Symptoms

  • CEL
  • Poor fuel economy
  • Rough idle
  • Increased emissions

Common causes

  • Aging sensor
  • Contaminated sensor
  • Exhaust leak
  • Fuel issues

Diagnostic steps

  1. Monitor sensor response time
  2. Check exhaust for leaks
  3. Test sensor heater
  4. Compare to specs

Repair notes

Replace A/F ratio sensor.

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Other Powertrain codes on this vehicle

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