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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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Repairs0Labor1038Torque1596Fluid17DTC3336Battery2Maintenance0Recalls5
P0409moderate severityPowertrain

Exhaust Gas Recirculation Sensor A Circuit

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

There is a fault in the EGR position sensor circuit. This prevents the PCM from knowing how far the EGR valve is open, affecting emissions.

Symptoms

  • Check engine light on
  • Rough idle
  • Failed emissions test

Common causes

  • Faulty EGR position sensor
  • Wiring or connector problems
  • Carbon-clogged EGR valve
  • Bad PCM

Diagnostic steps

  1. Read code and freeze frame data
  2. Inspect EGR sensor wiring and connector
  3. Test sensor voltage and ground
  4. Replace EGR sensor or valve as needed
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