Carbon buildup causing EGR to stick. Faulty EGR position sensor. Wiring fault to EGR valve. Vacuum leak to EGR actuator. Failed EGR valve motor.

Which cars are affected by P0404?

P0404 is most commonly reported on Vauxhall, Ford, Volkswagen, Renault, Fiat vehicles, but can appear on any make.

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P0404

Medium severity

EGR Control Circuit Range/Performance

The EGR valve position does not match what the ECM has commanded. The valve may be sticking, responding slowly, or the position sensor may be faulty.

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Common causes of P0404

1Carbon buildup causing EGR to stick

2Faulty EGR position sensor

3Wiring fault to EGR valve

+2 more causes

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Commonly affected vehicles

VauxhallFordVolkswagenRenaultFiat

P0404 can appear on any vehicle — these are the makes where it is most frequently reported.

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Related fault codes

P0171Medium

System Too Lean (Bank 1)

P0300High

Random/Multiple Cylinder Misfire Detected

P0420Medium

Catalyst System Efficiency Below Threshold (Bank 1)

P0172Medium

System Too Rich (Bank 1)