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1998 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1040Torque1596Fluid17DTC3336Battery2Maintenance0Recalls5
P0425moderate severityPowertrain

Catalyst Temperature Sensor (Bank 1, Sensor 1)

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The PCM detected a fault with the bank 1 catalyst temperature sensor circuit. This sensor monitors converter temperature for emissions control.

Symptoms

  • Check engine light on
  • Failed emissions test
  • Inaccurate temperature readings

Common causes

  • Faulty catalyst temperature sensor
  • Open or shorted wiring
  • Corroded connector
  • Faulty PCM input

Diagnostic steps

  1. Scan and confirm P0425
  2. Inspect sensor wiring
  3. Measure sensor signal
  4. Compare to expected values
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