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P0136moderate severityPowertrain

O2 Sensor Circuit Bank 1 Sensor 2

on 2015 Kia Forte 1.8L I4 · FWD

What this code means

General malfunction in the downstream O2 sensor circuit for Bank 1.

Symptoms

  • Check Engine Light
  • Failed emissions test
  • Reduced catalyst monitoring

Common causes

  • Faulty downstream O2 sensor
  • Wiring damage
  • Exhaust leak after catalyst

Diagnostic steps

  1. Test O2 sensor voltage
  2. Inspect wiring
  3. Check for exhaust leaks after cat

Repair notes

Replace downstream O2 sensor.

Other Powertrain codes on this vehicle

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