P0404 Code: Meaning, Causes, Symptoms & Fix Cost | AXLY.pro

Check Engine Code

P0404

Exhaust Gas Recirculation (EGR) Control Circuit — Range/Performance

Severity: medium DIY difficulty: 3/5 Typical cost: $60–$500

What P0404 means

P0404 means the ECM commanded the EGR valve to a position but the feedback signal doesn't match — the valve isn't opening/closing the way it should. It is usually a sticking, carbon-fouled valve or a bad position sensor rather than a full failure.

Symptoms

  • Check engine light on
  • Rough idle or hesitation (sometimes no noticeable symptoms)
  • Light pinging or surging under load
  • Occasional stalling

Likely causes (most common first)

  1. Carbon buildup binding the EGR valve
  2. Faulty EGR valve position sensor
  3. Sticking or failed electronic EGR valve motor
  4. Wiring or connector fault at the EGR valve

Can I keep driving?

Yes, short-term. Clean or replace the EGR valve when convenient — a stuck valve can eventually cause stalling or failed emissions.

Typical repair cost

DIY fixes can start near $60 (parts only). Shop repairs for P0404 typically run up to $500 depending on the underlying cause and vehicle. Start with the most common cause — Carbon buildup binding the EGR valve — before throwing parts at it.

Recommended parts & tools for P0404

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Related codes

P0401P0402P0405P0406

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