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1998 MAZDA 626
2.5L V6•FWD•AUTOMATIC•gas
6 active safety recalls on this vehicle — view recalls
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Repairs0Labor499Torque3168Fluid7DTC853Battery1Maintenance0Recalls6
P0404moderate severityPowertrain

EGR Control Circuit Range/Performance

on 1998 Mazda 626 2.5L V6 · FWD

What this code means

The EGR valve is not responding as commanded by the PCM.

Symptoms

  • Check Engine Light
  • Rough idle
  • Stalling
  • Poor performance

Common causes

  • Carbon restricting EGR valve movement
  • Faulty position sensor in EGR
  • EGR valve mechanically stuck

Diagnostic steps

  1. Command EGR open/closed with scan tool and monitor position
  2. Check for carbon restricting movement
  3. Test position sensor

Repair notes

Clean or replace EGR valve.

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