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2003 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas•3RZ-FE
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1047Torque1633Fluid17DTC3480Battery2Maintenance0Recalls5
P0674low severityPowertrain

Cylinder 4 Glow Plug Circuit

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

The PCM detected a fault in the glow plug control circuit for cylinder 4. This can cause hard starting and rough running in cold conditions on diesel engines.

Symptoms

  • Hard cold starting
  • Rough idle when cold
  • Glow plug warning light

Common causes

  • Faulty glow plug cylinder 4
  • Corroded glow plug wiring
  • Bad glow plug control module
  • Blown glow plug fuse

Diagnostic steps

  1. Scan for related glow plug codes
  2. Measure resistance of cylinder 4 glow plug
  3. Check wiring and connectors to glow plug
  4. Test glow plug control module output
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