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ENRUDEPLES

P0404 — Exhaust Gas Recirculation Control Circuit Range/Performance

moderate

What it means

The EGR circuit is electrically intact, but the valve does not follow the commanded position: the feedback from the position sensor differs from the target by more than the allowed tolerance, or it does not change at all. On electric valves the ECM compares the commanded duty cycle with the actual pintle position several times per second. Symptoms range from rough idle to hesitation and knocking, depending on whether the valve is stuck open or closed.

Likely causes (most common first)

  1. Heavy carbon build-up preventing the pintle from moving through its full travel
  2. Worn or contaminated EGR position sensor (potentiometer track)
  3. Sticking or mechanically damaged EGR valve
  4. High resistance in the wiring or connector, so the valve moves slower than commanded
  5. Blocked EGR passage that loads the valve and slows its response
  6. Software or adaptation issue after valve replacement without relearning

Can you drive with it?

You may drive to the workshop, but avoid long trips under heavy load.

This is the generic meaning. What about your car?

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